932-1005 Detector Participants Guide

Technical Training Participant’s Guide Integrated Genset Controls

932-1005 11/2000

Integrated Generator Set Controls

Introduction

Integrated Generator Set Controls Module Table of Contents Section 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I-1 The introduction describes the audience, the purpose, and the structure of the training module. Lesson: Fundamentals of Generator Set Controls

. . . . . . . . . . . . . . . . . . F-1

Participants review principles of generator set control systems. Lesson: Detector Control Front Panels

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Participants learn the standard and optional components in the Detector Control front panels. Lesson: Cummins / Onan Diagrams

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

Participants learn how to identify the different diagrams used by Cummins Power Generation and their uses. Lesson: DC Control Inputs & Outputs

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Participants learn to identify the components on the ECM board and their function, and the main input and output signals for the ECM. Lesson: Troubleshooting the DC Control

. . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Participants learn the sequence of operation of the Detector Control ECM and where to check for signals which indicate proper or improper function of the ECM. Lesson: Detector ECM Simulator

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Participants use the learning from the previous lessons to assemble and test the operation of a Detector Control. Lesson: Auxiliary Relay Board (ARB)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

Participants learn the components, function, and function of the jumpers on the ARB.

Cummins is a registered trademark of Cummins, Inc.

Participant’s Guide

I-1

Introduction

Integrated Generator Set Controls

Lesson: AC Control Inputs, Outputs, and Troubleshooting

. . . . . . . . . . 7-1

Participants learn to identify the components on the Automatic Voltage Regulator (AVR), their function, and the main input and output signals for the AVR. Lesson: Automatic Voltage Regulator Adjustments

. . . . . . . . . . . . . . . . . 8-1

Participants learn how to identify the different adjustment potentiometers on common Cummins/Onan AVRs and how to properly adjust the AVRs. Lesson: Alternator Reconnection Diagrams

. . . . . . . . . . . . . . . . . . . . . . . . 9-1

Participants learn how to reconnect alternator windings and interpret reconnection diagrams. Lesson: AC Control Troubleshooting

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-1

Participants learn how to troubleshoot the AC Control and alternator.

I-2

Participant’s Guide

Integrated Generator Set Controls

Introduction

Introduction Welcome!

Welcome to the Participant’s Guide for the Integrated Generator Set Control module! This guide was written by Cummins Power Generation’s Sales and Technical Training department for your use and reference. We suggest you read through the entire Introduction to become familiar with the guide’s structure. Then, just follow along in the guide during your training session.

Module Purpose

The purpose of the Integrated Generator Set Control module is to help you, the Cummins Power Generation distributor technician understand the use, operation, service and troubleshooting of the Integrated Generator Set Control. With this information, you will be better prepared to meet your customers’ varying needs.

Module Audience

This module was written for Cummins Power Generation distributor power generation technicians, and customer technicians, who have previous experience with or knowledge of Integrated generator sets.

Module Structure

This module contains lessons on related topics. Each lesson follows a carefully designed training format, including a warm up, presentation, and activity (or exercise). Lesson Format Warm ups help you focus and begin thinking about the lesson topic. The presentation portion of the lesson is where you receive new information. The activity follows the presentation; it gives you the chance to practice new skills or work with new ideas. Module Assessment After completing all the lessons in the module, you will complete a module assessment. The module assessment lets

Participant’s Guide

I-3

Introduction

Integrated Generator Set Controls

us evaluate the level of knowledge you have on the topic after completing the module. Module Comment Form You will also complete a module comment form. This form gives you the chance to comment on the usefulness and effectiveness of the training module and make suggestions for improvements. We will use the results from the module assessment and module comment form to help us determine if there is a need to modify the module.

I-4

Participant’s Guide

Integrated Generator Set Controls

Lesson: Generator Set Control Fundamentals

Lesson: Generator Set Control Fundamentals This lesson presents an overview of the Detector series of generator set controls.

Objectives After completing this lesson, you should be able to: • State the purpose of the generator set control. • State the purpose of the Automatic Voltage Regulator (AVR). • State the purpose of the Engine Governor. • List the main circuits of the ECM. • List the main functions of the Run circuit. • Describe what circuits and components are powered during the Start mode of operation, and what removes power to them. • State the point of change from Start to Run circuits in the Detector controls. • State when the oil pressure and coolant temperature can cause warnings or faults to appear. • State which faults can occur during the Start circuit operation. • List the inputs required to light the local and remote Run lamps.

Onan is a registered trademark of Onan Corporation.

Participant’s Guide

F-1

Lesson: Generator Set Control Fundamentals

Integrated Generator Set Controls

OHFĆ1

S&TT 10/00

Slide F-1 Detector-12 Generator Set Control

Generator Set Control Fundamentals Quiz 1.

What is the purpose of the generator set control?

2.

List three major circuits of a generator set control.

3.

List the control switch positions for manual and automatic operation. Manual: Automatic:

F-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: Generator Set Control Fundamentals

Three parts of a Genset Control

ECM

AVR

Governor Control

OHFĆ2

S&TT 10/00

Slide F-2 Detector-12 Generator Set Control and Engine

What does a generator set control do? Automatic Voltage Regulator (AC Control) • Monitors Generator Set Output Voltage. • Controls Excitation to Alternator. • Protects AVR and Alternator Wiring. Engine Control Monitor (DC Control) • Monitors Engine Operation. • Protects Engine if Oil Pressure or Coolant Temperature go out of normal range. Engine Governor Control • Maintains steady engine speed when load is increased and decreased

Participant’s Guide

F-3

Lesson: Generator Set Control Fundamentals

Integrated Generator Set Controls

DC Start Circuits

ECM

OHFĆ3

S&TT 10/00

Slide F-3 DC Start Circuits

The DC Start Circuit Engine Systems •

Fuel System

•

Ignition System

•

Governor System

•

Cranking Solenoid and Motor

•

Monitor Primary Faults

Cooling System •

Dampers and Louvers

•

City Water Cooling

F-4

Participant’s Guide

Integrated Generator Set Controls

Lesson: Generator Set Control Fundamentals

DC Run Circuits

ECM

OHFĆ4

S&TT 10/00

Slide F-4 DC Run Circuits

The Run Circuits Starter Disconnect Signals DC Starter Disconnect (DC Alternator - Cummins sets) (Generator RPM pickup - Kubota sets) AC Starter Disconnect (TB21-21 & TB21-32) Local Run Light = Two Starter Disconnect Signals

Remote Run Light = AC Starter Disconnect Signal

Participant’s Guide

F-5

Lesson: Generator Set Control Fundamentals

Integrated Generator Set Controls

DC Stop Circuit

ECM

OHFĆ5

S&TT 10/00

Slide F-5 DC Stop Circuit

The DC Stop Circuit: Shutdown When the Operator moves S12 to the Stop position, A11 K7 and A11 K2 are de-energized, This removes Switched B+ from Engine Terminal 26. When Switched B+ is removed from T-26, the Fuel, Governor and Ignition systems are turned off. The Diesel engine stops because the fuel is turned off. The Gasoline or Gaseous fuel engine stops because the fuel and ignition systems are turned off.

F-6

Participant’s Guide

Integrated Generator Set Controls

Lesson: Generator Set Control Fundamentals

DC Faults

ECM

OHFĆ6

S&TT 10/00

Slide F-6 DC Faults

The DC Stop Circuit: Faults STANDARD MONITOR

INFORM Alarms

OPTIONAL PROTECT Faults

MONITOR

INFORM Alarms

PROTECT Faults

Remove Switched B+ from: Stops genset on:

Participant’s Guide

F-7

Lesson: Generator Set Control Fundamentals

Integrated Generator Set Controls

Genset Control Introduction Quiz 1

What is the purpose of the generator set control?

2.

List the three main circuits of the ECM.

3.

List the three key functions of the RUN circuit.

4.

The START mode of the ECM provides power to what components and/or circuits?

5.

What is the change-over point from the START circuit to the RUN circuit?

6.

When does the ECM start looking at Oil Pressure and Coolant Temperature for warnings and faults?

7.

What removes the starter pilot signal when the engine reaches approximately 350 – 550 RPM?

8.

What is the fault that occurs if the control does not get an AC or DC starter disconnect signal?

9.

What signals tell the Engine Control Monitor (ECM) to check the engine for low oil pressure, and when?

10.

What is required to have the local RUN lamp light?

F-8

Participant’s Guide

Integrated Generator Set Controls

Lesson: Detector Control Front Panels

Lesson: Detector Control Front Panels This lesson presents an overview of the Detector Control front panels.

Objectives After completing this lesson, you should be able to: • Identify standard and optional components on Detector Controls. • Describe the numbering system used inside the Detector Control. • Identify the components which come as part of the Meter Kit. • Identify those AC panel components which must be ordered separately from the Meter Kit.

Cummins is a registered trademark of Cummins, Inc.

Participant’s Guide

1-1

Lesson: Detector Control Front Panels

Integrated Generator Set Controls

Detector 7 Control DS11

A12

M11 CB21

S12 S11 M12

M13 M14

AC Control

OHIĆ1

DC Control

S&TT 10/00

Slide 1-1 Detector-7 Control

Detector Control standard components In the blanks below, fill in the designation of the component which matches the description next to the blank. Lamp Test/Reset switch Run/Stop/Remote switch Panel Lamp Indicator Lamp bar (7 lights) Oil Pressure gauge Water Temperature gauge Battery Voltmeter Running Time meter 1-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: Detector Control Front Panels

Detector 12 AC Control Panel R21

DS21 DS22

M21

M22

M23

S21

M25

M24

OHIĆ2

S&TT 10/00

Slide 1-2 Detector-12 AC Control Panel

Optional AC Control items: In the blanks below, fill in the designation of the component which matches the description next to the blank. * = Included in the Meter Package with a new door and wiring harness. *

AC Voltmeter. AC Ammeter.

*

Frequency meter.

*

Adjust voltage ±5%.

*

Tell Operator to read proper meter scale (upper or lower).

*

Switch Ammeter and Voltmeter to different output phases. Wattmeter. Power Factor meter.

Participant’s Guide

1-3

Lesson: Detector Control Front Panels

Integrated Generator Set Controls

Detector 12 DC Control Panel

A12

R11 M15

M17

OHIĆ3

M16

S13

S&TT 10/00

Slide 1-3 Detector-12 DC Control Panel

Other optional DC Control components: All 12 lamps Engine Oil Temperature gauge. Tachometer. Turbocharger Pyrometer. Engine speed adjust pot. Emergency Stop switch.

1-4

Participant’s Guide

Integrated Generator Set Controls

Lesson: Detector Control Front Panels

Detector Front Panel Quiz Complete the following quiz to check on your knowledge of the Detector Control front panel components. 1.

What component comes standard on ALL Detector Controls? A. S13 B. CB12 C. CB21 D. M21

2.

What component does not come as part of the Meter Kit? A. M21 B. M22 C. R21 D. S21

3.

What component tracks engine operation for oil changes? A. M11 B. M12 C. M13 D. M14

4.

Which switch has a lamp in it to indicate resetting of the control is needed? A. S11 B. S12 C. S13 D. S21

5.

Which optional component indicates engine exhaust temperature? A. M12 B. M13 C. M15 D. M17

6.

Which component has either seven or twelve lamps installed? A. A11 B. A12 C. A13 D. A14

Participant’s Guide

1-5

Lesson: Detector Control Front Panels

Integrated Generator Set Controls

This page intentionally left blank

1-6

Participant’s Guide

Integrated Generator Set Controls

Lesson: Cummins/Onan Diagrams

Lesson: Cummins/Onan Diagrams This lesson presents an overview of the different types of diagrams used with Cummins/Onan and Cummins Power Generation products.

Objectives After completing this lesson, you should be able to: • Identify a diagram by its number and designation. • List four different types of Cummins/Onan diagrams. • Read and interpret Cummins/Onan wire markings. • Describe when you would use each type of diagram. • Select and use all types of Cummins/Onan diagrams.

Cummins is a registered trademark of Cummins, Inc. Onan is a registered trademark of Onan Corporation.

Participant’s Guide

2-1

Lesson: Cummins/Onan Diagrams

Integrated Generator Set Controls

Block Diagram AUXILIARY TERMINAL BOARD VOLTAGE REGULATOR (VR21)

MAIN STATOR

EXCITER STATOR

MAIN ROTOR

EXCITER ROTOR

MAIN STATOR

EXCITER STATOR ROTATING DIODES

OH2Ć1

S&TT 10/00

Slide 2-1 Block diagram

Block diagrams are used to show an overall view of a system or major component. Block diagrams show the system or component in a much larger scale than is used in any other Cummins/Onan diagram. To use these other diagrams effectively you must learn how to read the diagrams. The purpose of each of these diagrams is different, and they should not be substituted for each other. You must use the proper diagrams for your specific equipment to be totally accurate. Interconnection Diagram Tells technicians or installers how to install and connect components. Wiring Diagram Used to put the equipment together correctly. Schematic Diagram Used to design the functions of the equipment and sell equipment to the customer. Reconnection Diagram Shows where the alternator output wires and the sensing wires connect for each generator set output voltage. 2-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: Cummins/Onan Diagrams

Interconnection Diagram

To annunciator

OH2Ć2

S&TT 10/00

Slide 2-2 Interconnection Diagram

Interconnection diagrams are used with kits or when connecting equipment to create a system. One of the most common installation diagrams is 630-1345.Wiring diagrams are designed to be used when you have to replace a part or a wiring harness in a piece of equipment in the field. When connecting a transfer switch and generator set together in the field you would use an interconnection diagram. Interconnection Diagrams show: Point-to-point wiring connections between components. Relative position of all connections on the parts inside the equipment. Notes and tabulations which are important for the installation to be successful. Tabulations showing size, length and type of wire to be used.

Participant’s Guide

2-3

Lesson: Cummins/Onan Diagrams

Integrated Generator Set Controls

Wiring Diagram

LEFT DOOR - REAR VIEW TB21-21 CB21-2 TB21-23

R21

TB21-32

TB21

VR21-5

VR21-3

CB21-1

VR21-1

VR21-2

VR21-8

M23 VR21-7

TB21-22

CB21

VR21-2

VR21

OH2Ć3

S&TT 10/00

Slide 2-3 Wiring Diagram

Wiring diagrams are used when building equipment at the factory, and when tracing wiring in the field. These diagrams show where each end of the wires connect. When replacing a wiring harness in the field, you would use a wiring diagram. Wiring Diagrams show: Inside view of all panels and control boxes. Point-to-point wiring connections. Relative position of all connections on the parts inside the equipment. Exploded views of sheet metal parts. Optional parts and wiring as dashed lines.

2-4

Participant’s Guide

Integrated Generator Set Controls

Lesson: Cummins/Onan Diagrams

CPG Wire Markings VR21 VR21-3 TB21–23

TB21-21 CB21-2

VR21-3

1 2 3 4 5 6 7 8 9 10

TB21–23

TB21-23 TB21-32 R21-1 R21-2

2

TB21

VR21-5

VR21-1 CB21-1 VR21-3

TB21-22

VR21-2

1

1

VR21-8

CB21 2

VR21-7

R21

21 22 23 24 25 26 27 28 29 30 31 32

OH2Ć4

S&TT 10/00

Slide 2-4 Wire Markings on a Cummins/Onan Wiring Diagram

All wires used in Cummins / Onan generator sets are marked on both ends with where the wire connects. The marking closest to the end of the wire shows where that end connects. The marking farthest away from the end of the wire shows where the other end connects. When connecting wires, use only the marking closest to the end in your hand. Do not pay attention to the other marking—unless the wire is in the harness backwards. If the markings are worn off one end of the wires, by reading the markings on the wire you can find the other end of the correct wire to use .

Participant’s Guide

2-5

Lesson: Cummins/Onan Diagrams

Integrated Generator Set Controls

Wire Marking Worksheet Using the wiring diagram shown on the previous page, fill in the following information: What is printed on the wire ends shown in slide 2-4 on the previous page?

Component

Marking at Left End of Wire

CB21-1

CB21-1

CB21-2

CB21-2

R21-1

R21-1

R21-2

R21-2

VR21-1

VR21-1

VR21-2

VR21-2

VR21-3

VR21-3

VR21-5

VR21-5

VR21-7

VR21-7

VR21-8

VR21-8

TB21-21

TB21-21

TB21-22

TB21-22

TB21-23

TB21-23

TB21-32

TB21-32

2-6

Marking at Right End of Wire

Participant’s Guide

Integrated Generator Set Controls

Lesson: Cummins/Onan Diagrams

Schematic Diagram

OH2Ć5

S&TT 10/00

Slide 2-5 Schematic Diagram (Detector AC Control without meters)

This diagram is a schematic of the AC Control for a Cummins/Onan generator set which does not have the optional meter package installed on the Detector Control. Component Identification: • CB21

Field Breaker

• G21

AC Generator

• VR21

AVR

• TB21

AC Control terminal board

Participant’s Guide

2-7

Lesson: Cummins/Onan Diagrams

Integrated Generator Set Controls

Operational Schematic Diagram

Rotating Diodes

Exciter Rotor

Main Rotor (–)

(+) L1

Exciter Stator

Main Stator

XX (–)

Excitation Out

AVR

X (+)

L3

Reference Voltage In L0

K1 CB21

K2

Regulator Drive Voltage In

OH2Ć6

L2 S&TT 10/00

Slide 2-6 Schematic Diagram of generator operation

Schematic diagrams show the operation of a an item of equipment or a system. Schematic diagrams are designed to be used when you have to troubleshoot a piece of equipment in the field. Normally schematic diagrams will show the input and output pin numbers for signal tracing. Schematic Diagrams show: Sequence of operation of the circuit or component. Input and Output wiring connections. All needed connections on the parts inside the equipment. Selected parts on circuit boards. Signal flow of circuit components.

2-8

Participant’s Guide

Integrated Generator Set Controls

Lesson: Cummins/Onan Diagrams

Reconnection Diagram CT21

SCHEMATIC DIAGRAM

PMG

CT22

U6

V2

U2

AC GEN VOLTAGE

L2 (V)

V6

V1

EXC FIELD

L1 (U)

K2K1P2P3P4S2S1A2A1XXXX X 8 7 6 3 2 1

U5 U1 W5

V5

AUXILIARY TERMINAL BLOCK

L0 (N)

W1

K2K1P2P3P4S2S1A2A1XXXX X 8 7 6 3 2 1 W6

CT23

W2

WIRING DIAGRAM 4 5 6 7 8

U5 V5 W5 W2 V2

N W V U

U2

TB21

VOLTAGE REG & OVERSPEED

L3 (W)

VOLTAGE REG

CONTROL INPUT - 12 LEAD U1 V1 W1 W6 V6 U6

CONTROL INPUT TB21 22 23 24

AUX TERM CON 8 7 6

SERIES DELTA 8 7 4

PARALLEL STAR 8 7 4

SERIES DOUBLE STAR DELTA 8 8 7 7 4 4

25 26

-

6 5

6 5

6 5

6 5

JUMPER

-

Ċ

Ċ

Ċ

Ċ

OH2Ć7

S&TT 10/00

Slide 2-7 Reconnection Diagram

Reconnection diagrams show how to connect the alternator output wires, current transformer secondary windings and sensing leads. Reconnection diagrams are designed to be used when you have to check or change the output voltage of a generator set in the field. Reconnection Diagrams show: Whether the generator is reconnectable, what output voltages and frequencies can be used, and how the output wires are marked. Current Transformer secondary connections. Schematic diagram of generator wiring connections (Wye, Delta). Wiring diagram of output connections from the reconnection studs to the auxiliary terminal block (with or without transformer connections). TB21 connections with different control inputs. Where to connect voltage reducing transformers used on non-reconnectible and medium voltage generator sets. Participant’s Guide

2-9

Lesson: Cummins/Onan Diagrams

Integrated Generator Set Controls

Cummins/Onan Diagram Quiz Work with the other people in your work group to complete this worksheet. 1. Which diagram is used when replacing a DC control wiring harness?

2. Which diagram shows the technician how to wire the current transformer secondary terminals?

3. Which diagram would be used to check inputs and outputs of a circuit board?

4. Which diagram would show the most general view of a system?

5. Which page of a 2-page circuit board diagram shows the parts on the board?

6. Which page of a 2-page circuit board diagram shows the circuits on the board?

7. Where would a technician find the nomenclature of a part used on a diagram?

8. What wiring diagrams show the size of wire to be used when connecting several components?

9. In the slide shown on page 2-3, what polarity of voltage is used as a remote start signal with the Detector-12 Control?

10. What type of diagram would be used with a reconnection diagram to find which terminals on a voltage regulator are used for reference voltage input and excitation voltage output?

2-10

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Inputs and Outputs

Lesson: DC Control Inputs and Outputs This lesson presents an overview of the DC Control Engine Monitor Board (ECM) inputs, outputs, fuses and jumpers.

Objectives After completing this lesson, you should be able to: • Identify the connectors on the A11 Engine Control Monitor (ECM) board. • Identify the functions of the A11 ECM fuses. • Identify the Inputs and Outputs of the A11 ECM board. • Identify the most important components on the A11 ECM. • State expected polarity of A11 ECM input and output signals. • State when a specific signal is expected as an input or output of the A11 ECM. • Identify A11 ECM Jumpers.

Cummins is a registered trademark of Cummins, Inc.

Participant’s Guide

3-1

Lesson: DC Control Inputs and Outputs

Integrated Generator Set Controls

Older ECM Connectors F4

P4

F1 F2 TB1 10 9 8 7 6 5 4 3 2 1

F5

F3

P3

TB2

1 2

3

4

5

P1

6 7

8 9 10 11 12 13 14 15 16 P2

OHIĆ1

S&TT 10/00

Slide 3-1 Older A11 ECM Connections and Fuses

Connectors TB1 TB2 P1 P2 P3 P4

Customer Inputs and Outputs Customer Inputs and Outputs Start Disconnect Inputs, Ground Input, engine sender Inputs Engine Warning and Shutdown Inputs Connections to A12 Lamp assembly Connections to front panel components

F1 F2 F3 F4 F5

20 Amps for Starter signal 20 Amps for Switched B+ 15 Amps for Battery Charger or Transfer Switch 5 Amps for A11 operation 5 amps for engine gauges

Fuses

3-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Inputs and Outputs

Main Components

ÉÉÉ ÉÉÉ ÉÉÉ ÉÉÉ ÉÉÉÉÉÉÉÉ ÉÉ ÉÉ ÉÉ

U1

K2

10 9 8 7 6 5 4 3 2 1

K3

K7

VR1

K12

ÉÉ ÇÇÇ ÉÉ ÇÇÇ ÉÉ ÇÇÇÉÉ ÇÇÇÉÉ K10

K6

K14

ÉÉ ÉÉ K1

1 2

3

4

5

6 7

P1 OHIĆ2

8 9 10 11 12 13 14 15 16 P2 S&TT 10/00

Slide 3-2 A11 ECM Components

Important Relays K1 K2 K3 K6 K7 K10 K12 K14

Oil Pressure Time Delay relay. Switched B+ relay. Starter relay. Latching Fault relay. A11 Run relay. AC Starter Disconnect relay. Cycle Crank relay. DC Starter Disconnect relay.

Other Components VR1 U1

DC Supply Surge Suppressor. Cycle Crank Timer chip

Participant’s Guide

3-3

Lesson: DC Control Inputs and Outputs

Integrated Generator Set Controls

Older ECM Jumpers

W3

10 9 8 7 6 5 4 W8 A 3 A 2 W9 1 P1

W4

A

A

W5 B

C A

D

C A

W1

1 2

W6

W7

B

B

B

W2

3

4

5

6 7

8 9 10 11 12 13 14 15 16 P2

OHIĆ3

S&TT 10/00

Slide 3-3 A11 ECM Jumpers

Moveable Jumpers W1 W2

W6 W7 W8 W9

Customer Fault 2 selection jumper. Customer Fault 1 selection jumper. “A” = Non-Timed Warning “B” = Non-Timed Shutdown “C” = Timed Warning “D” = Timed Shutdown “A” sets Pre-High Coolant Temperature to Alarm mode “A” sets Pre-Low Oil Pressure to Alarm mode. Customer Fault 2 selection jumper. Customer Fault 1 selection jumper. “A” = Warning when running or stopped. “B” = W1 & W2 are used to select Warning or Shutdown.

Solderable Jumpers W3 / W4 W5 3-4

Factory set in “B” position. Move to “A” position for Ground to start input signal. Factory set in “A” position for cycle cranking. Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Inputs and Outputs

New ECM with LEDs

TB3

W10

OHIĆ4

S&TT 10/00

Slide 3-4 NEW Detector Board showing LED, new jumpoer, and TB3 placement

LEDs DS1 DS2 DS3 DS4 DS5 DS6 DS7 DS8 DS9

B+ connected Run mode Start Command Crank output DC start disconnect AC start disconnect LOP/HET enabled Reverse battery polarity Remote/Emergency stop

Green Green Green Green Green Green Green Red Red

Other functional Additions Include: SW OFF FLASHER Jumper (W10) Customer request for a jumper inserted in the sw off flasher circuit to have three options for the light; disabled, flashing, or constant. ADD THREE TERMINAL BLOCK–START/STOP/REMOTE SW For diagnostic purposes. P3 and P4 connectors have been a source of warranty claims due to poor contact continuity. Connector cannot be changed in field without changing mating connector. Terminal block allows alternative connection to functions as a field test feature, or could be hard wiring if desired.

Participant’s Guide

3-5

Lesson: DC Control Inputs and Outputs

Integrated Generator Set Controls

Inputs & Outputs

10 9 8 7 6 5 4 3 2 1

1 2

3

4

5

6 7

P1

8 9 10 11 12 13 14 15 16 P2

OHIĆ5

S&TT 10/00

Slide 3-5 A11 ECM Inputs and Outputs — Run and Remote modes

TB1 Inputs: B+

Unfused Battery B+ input.

RMT

B+ input from transfer switch for automatic operation. This is the only terminal not used for both operating modes.

TB1 Outputs:

3-6

B+

Fused by F3 for B+ output to Transfer Switch or Battery Charger.

Ground

Ground return for Battery Charger.

Starter

Fused by F1 for B+ output to the starter solenoid.

SW B+

Fused by F2 for Switched B+ output for “RUN” circuit. Governor, Ignition and Fuel systems

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Inputs and Outputs

Inputs & Outputs

10 9 8 7 6 5 4 3 2 1

1 2 P1

3

4

87654321

5

6 7

8 9 10 11 12 13 14 15 16 P2

OHIĆ6

S&TT 10/00

Slide 3-6 A11 ECM Required Inputs

P1 / J1 Required Input signal: Main GROUND input from ground stud in control box. Run circuit Input signals: 90-120 VAC input for AC Starter Disconnect signal. B+ input from for DC Starter Disconnect signal. This can come from several places: Battery Charging Alternator enters P1-3 (300-2809 — 300-2812) DKA-Series gensets enters P1-5 from Overspeed Module (300-4294 —300-4297)

Participant’s Guide

3-7

Lesson: DC Control Inputs and Outputs

Integrated Generator Set Controls

Inputs & Outputs

10 9 8 7 6 5 4 3 2 1

1 2 P1

3

4

5

6 7

8 9 10 11 12 13 14 15 16

87654321

P2

654321

OHIĆ7

S&TT 10/00

Slide 3-7 A11 ECM Warning and Shutdown Inputs

P2 / J2 Input signals (Alarms and shutdowns): Low Engine Temperature (less than 70° F.) Low Oil Pressure shutdown. High Engine Temperature shutdown. Pre-Low Oil Pressure Alarm. Pre-High Engine Temperature Alarm. Overspeed shutdown. TB1 shutdown Input Overspeed input from PMG Frequency Detection Module.

3-8

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Inputs and Outputs

Inputs & Outputs

10 9 8 7 6 5 4 3 2 1

1 3 5 7 9 11 13

1 2 P1

3

4

5

6 7

P3

8 9 10 11 12 13 14 15 16

87654321

P2

654321

OHIĆ8

S&TT 10/00

Slide 3-8 A11 ECM Outputs to A12 Lamps

P3 / J3 Output signals for Detector-7 Controls: B+ to all lights on A12 assembly. Fused by F4. Ground output for RUN lamp. Ground output for Overcrank shutdown lamp. Ground output for Overspeed shutdown lamp. Ground output for High Engine Temperature shutdown lamp. Ground output for Low Oil Pressure shutdown lamp. Ground output for Pre-High Engine Temperature Alarm lamp. Ground output for Pre-Low Oil Pressure Alarm lamp.

Participant’s Guide

3-9

Lesson: DC Control Inputs and Outputs

Integrated Generator Set Controls

Inputs & Outputs

1 3 5 7 9 11

10 9 8 7 6 5 4 3 2 1

1 2 P1

3

4

5

87654321

6 7

8 9 10 11 12 13 14 15 16 P2

654321

OHIĆ9

S&TT 10/00

Slide 3-9 A11 ECM Front Panel Inputs and Outputs

P4 / J4 Major Input and Output signals: Switched B+ output from F5 for engine gauges. B+ input to K7 from S12 terminal 2. B+ output to S12 terminal 3 for RUN operation. B+ output to S12 terminal 1 from TB1-6 and F3 for automatic operation.

3-10

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Inputs and Outputs

Inputs & Outputs

10 9 8 7 6 5 4 3 2 1

1 2 P1

3

4

5

6 7

8 9 10 11 12 13 14 15 16

87654321

P2

654321

OHIĆ10

S&TT 10/00

Slide 3-10 A11 ECM Inputs at TB2

TB2 Input signals: All are Ground potential. FLT2 — latches FLT2 relay. FLT1 — latches FLT1 relay. Lamp Test / Fault Reset from paralleling system. Low Day Tank level. Emergency Stop shutdown.

Participant’s Guide

3-11

Lesson: DC Control Inputs and Outputs

Integrated Generator Set Controls

Inputs & Outputs

10 9 8 7 6 5 4 3 2 1

1 2 P1

3

4

5

6 7

8 9 10 11 12 13 14 15 16

87654321

P2

OHIĆ11

654321 S&TT 10/00

Slide 3-11 ECM Annunciator Outputs

TB2 Output signals (Annunciation): All are Ground potential. FLT2 FLT1 Overcrank Overspeed. High Engine Temperature shutdown Low Oil Pressure shutdown Pre-High Engine Temperature Alarm Pre-Low Oil Pressure Alarm Switch Off (Not in Auto) Low Engine Temperature Alarm Low Day Tank level

3-12

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Inputs and Outputs

A11 ECM Connection Quiz Select the best answer for each question from the choices given. 1.

Where does the ground signal enter the A11 ECM? A. B. C. D.

2.

Where does the Battery B+ signal enter the A11 ECM? A. B. C. D.

3.

P4-5 P4-6 P4-8 P4-9

Which fuse on the A11 ECM board could be bad if the A12 lamps do not light when S11 is moved to the Lamp Test/Reset position? A. B. C. D.

6.

TB1-7 TB1-8 TB1-9 TB1-10

Where does the Switched B+ signal leave the A11 ECM for the Oil Pressure Gauge? A. B. C. D.

5.

TB1-7 TB1-8 TB1-9 TB1-10

Where does the Battery signal leave the A11 ECM for use as a remote start signal by the transfer switch? A. B. C. D.

4.

P1-1 P1-4 P1-6 P1-8

F2 F3 F4 F5

Which fuse being bad would cause the EFC Governor not to operate? A. B. C. D.

F2 F3 F4 F5

Participant’s Guide

3-13

Lesson: DC Control Inputs and Outputs

7.

Where does the Low Oil Pressure shutdown enter and leave the A11 ECM? A. B. C. D.

8.

TB2-1 TB2-2 TB2-4 TB2-5

What relay latches whenever a shutdown condition input is present? A. B. C. D.

3-14

TB2-1 TB2-2 TB2-4 TB2-5

Where could a remote reset signal be connected to the A11 ECM to reset Warnings? A. B. C. D.

12.

TB1-1 TB1-2 TB1-3 TB1-4

Where could the customer connect a Day Tank Rupture Basin contact so the genset would shut down if the contacts closed? A. B. C. D.

11.

TB1-1 TB1-2 TB1-3 TB1-4

Where can you check for an output that is present only when the AC Start Disconnect is present? A. B. C. D.

10.

P2-2 / TB2-3 P2-3 / TB2-6 P2-4 / TB2-9 P2-5 / TB2-12

Where can an alternate Overspeed signal enter the A11 ECM? A. B. C. D.

9.

Integrated Generator Set Controls

K1 K2 K6 K7

Participant’s Guide

Integrated Generator Set Controls

13.

What relay allows the ECM to monitor the oil Pressure and Coolant Temperature? A. B. C. D.

14.

Customer FLT1 & FLT2 Cycle Crank or Continuous Crank Oil Pressure TD High Engine Temp. TD

What position does W2 have to be in for FLT1 to be a non-timed shutdown? A. B. C. D.

18.

120 VAC Ground Switched B+ B+

What time delay is selected or not selected with jumpers W1 and W2? A. B. C. D.

17.

90 VAC 100 VAC 110 VAC 120 VAC

What signal is present at TB1-3 or P4-1 when the AC Starter Disconnect is connected to the ECM? A. B. C. D.

16.

K1 K2 K6 K7

What maximum value of signal is expected as an AC Starter disconnect? A. B. C. D.

15.

Lesson: DC Control Inputs and Outputs

A B C D

What A11 jumper can select Pre-Low Oil Pressure as a shutdown instead of a warning? A. B. C. D.

W3 W4 W6 W7

Participant’s Guide

3-15

Lesson: DC Control Inputs and Outputs

19.

Which jumper allows the customer to have continuous cranking instead of cycle cranking? A. B. C. D.

20.

W3 W4 W5 W6

What remote start input is expected on a 350DFCC ECM with factory settings? A. B. C. D.

3-16

Integrated Generator Set Controls

Ground +12 Volts +24 Volts 120 VAC

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the DC Control

Troubleshooting the DC Control This lesson presents an overview of troubleshooting the Detector Control Engine Control Monitor (ECM) board.

Objectives After completing this lesson, you should be able to: • Identify input and output signals and their polarity in a static state. • Identify input and output signals and their polarity when the ECM is operated from the front panel with S12 in the “RUN” position. • Identify input and output signals and their polarity when the ECM is operated from a remote device with S12 in the “REMOTE” position. • Describe the sequence of operation inside the Detector Control. • Identify the fuses needed to operate the genset in each operating mode.

Cummins is a registered trademark of Cummins, Inc.

Participant’s Guide

4-1

Lesson: Troubleshooting the DC Control

Integrated Generator Set Controls

Old Detector ECM – 300-2812

OH4Ć1

S&TT 10/00

Slide 4-1 Older Detector ECM – 300-2812 and its replacements

Originally designed in 2-Light and 12-Light versions for 12 Volt and 24 Volt systems. Early boards had glass cartridge fuses, later boards had automotive-type fuses. VR1 was a reverse polarity battery protection for the board circuits. Early VR1 was a Zener diode, later changed to an MOV. Early boards had black relays for K2 and K3 with removable covers. Later versions had sealed, white relays for K2 and K3.

4-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the DC Control

New Detector ECM – 300-4692

OH4Ć2

S&TT 10/00

Slide 4-2 New Detector ECM – 300-4296

The latest Detector ECM has nine LEDs which indicate board operation. DS1 DS2 DS3 DS4 DS5 DS6 DS7 DS8 DS9

B+ Input Run B+ Start Crank Crank Output DC Start Disconnect AC Start Disconnect LOP / HET Enable Reverse Battery Remote Shutdown

Green Green Green Green Green Green Green Red Red

There is a separate terminal Board (TB3) which has three terminals for an input to provide the following functions: TB3-1 TB3-2 TB3-3

Participant’s Guide

Remote Start Lamp Test / Reset Manual Run

B+ Input Ground Input B+ Input

4-3

Lesson: Troubleshooting the DC Control

Integrated Generator Set Controls

Troubleshooting Hints Questions to ask before and during troubleshooting: What does the control do correctly? What does the control not do? Where should there be input signals? What type of voltage are they? What level of voltage are they?

AC / DC

Where should there be output signals? What type of voltage are they? What level of voltage are they?

AC / DC

Suggested DC Control Troubleshooting Sequence 1. A.

Gather Information. Lights / Switches What alarm or Shutdown lights are lit? Where are the switches positioned? Is there a remote Emergency Stop switch? These will give you an idea of where to start your troubleshooting efforts.

B.

People. What was happening just before this problem occurred? Were suspicious sounds head or smoke seen in the area of the genset? Was someone near the genset who normally does not come into the area? Who had access to the set?

C.

Visual Inspection. With the genset stopped check genset fluids, battery electrolyte and voltage, generator and load connections, circuit breaker connections and handle position, and connections inside the generator set control box. Check fuses on the ECM and switch positions on the front of the genset control box.

D.

Operational Check. Attempt to start the set and verify the complaint on your work order. Listen to the engine sounds when starting and after starter disconnect occurs. With the genset running (at idle if appropriate) check oil pressure, coolant temperature, engine and generator sounds and cooling air.

4-4

Participant’s Guide

Integrated Generator Set Controls

E.

Lesson: Troubleshooting the DC Control

Other Sources Of Information. What entries are in the maintenance log for the set? What was the last part replaced — does that part have any connection to the present problem? Check the last repair or kit installation to make sure the set was left in operational condition.

2. A.

Analyze The Information (Think!) Use Your Knowledge Of The System(s). Use your previous repair and troubleshooting experiences to think of some possible causes for this problem.

B.

Troubleshooting Charts. Look at the troubleshooting charts in the Operator’s Manual and Service Manual to see what checks are recommended by the factory for this problem. Remember, many people worked to develop the troubleshooting charts in the manuals, and their experiences might help you repair this set.

C.

Decide On Tests To Perform. Using the troubleshooting charts, decide on what tests to perform and what you should see if the results of these tests are good or bad. Perform the tests and write down what you found from the tests. Writing down the results will help you remember what you tested, when you tested it, and the results of the test.

D.

Common Point Analysis. If several operations or circuits are affected, look for only those things that affect both of the operations or circuits. If the genset cranks but does not start, and the electronic governor actuator does not move during cranking, check the engine gauges to see if A11 K2 is working.

E.

Use Wiring Diagrams. If you cannot find the answer to the problem in the Operator’s Manual or the Service Manual, you will have to go to the prints for the genset and the control. It may help you to refer to the sequence of operation of the control in the Service Manual while you look at the prints. Again, write down what you want to check and the results of the check. If you find you are checking the same point for the third time, you might be looking for the wrong thing.

Participant’s Guide

4-5

Lesson: Troubleshooting the DC Control

3. A.

Integrated Generator Set Controls

Perform Tests To Isolate Actual Cause Of Problem From Possible Causes Of Problem. Voltage Checks. Check for proper input and output signals at the ECM terminal blocks and connectors. Check on schematic and wiring diagram for location and estimate desired signal.

B.

Jumper Lead Checks. Use a jumper lead to connect B+ or Gnd to one end of a component like a relay to see if you can force the component to operate.

C.

Continuity Checks. Check the quality of the connection through a component or connector with an ohmmeter.

D.

Substitution. If you cannot bypass surrounding components or wiring, temporarily replace the suspected component with a known good component. If the substitution does not change the operation, replace the original component before going on to the next step. If you change more than one variable in a circuit at a time, you may not know which change made the system operate properly.

5. A.

Retest. Assures Problem Is Fixed. Check the genset to make sure the reported problem is fixed.

B.

Assures No Additional Problems Exist Or Have Been Caused During Repairs. Check all operations of the genset to make sure that something has not failed during the testing and repair process.

C.

Assures System Is Operational. Make sure all parts of the ECM system operate properly.

4-6

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the DC Control

ECM Static State Checks B+ Unfused Battery B+ enters the ECM at TB1-9. If Fuse F3 is good, Battery B+ will be available at TB1-7 for accessories whenever the batteries are connected. DS1 will be lit if the ground wire is connected. DS8 will be lit if the B+ and ground wires are connected backward. Ground The main ground enters the ECM at P1-6 from the ground stud inside the ECM cabinet. The main ground leaves the ECM for a transfer switch or other remote battery charger at TB1-5

Participant’s Guide

4-7

Lesson: Troubleshooting the DC Control

Remote

Integrated Generator Set Controls

P4

TB1 6

5 9 F5

Sw. B+

10 9

B+ In

DS4

Starter

8

B+ Out B+ Out (Shutdown)

7

DS3

K2

F2

K7

F3

DS8

K6

4

Ground Output

5

Gnd when AC Start Disconnect is present

3

S12

K7

P3

K3

K10

K14 DS6

K14

Run

13

B+ to A12 Lamps

5

A12 RUN Lamp

DS2

K2 K10

Off

DS1 lit if B+ correct polarity DS8 lit if B+ incorrect polarity

K6

K12 K10 K14

DS9

Remote

6

F4

K3

F1

DS1

7

To Gauges

K10 DS5

P1

OH4Ć3

6

Ground Input

3

2

1

DC AC Start Disconnects

DS7 is connected to the W6 & W7 jumpers

Slide 4-3 ECM Static State Checks

DS1 DS2 DS3 DS4 DS5 4-8

B+ Connected Run Mode Start Command Crank Output DC Start Disconnect

DS6 DS7 DS8 DS9

AC Start Disconnect LOP/HET Enabled Reverse Battery Polarity Remote/Emergency Stop

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the DC Control

ECM Manual Operation Mode Checks B+ Battery B+ enters the ECM at TB1-9. If Fuse F3 is good, Battery B+ will be available at TB1-7 for accessories whenever the batteries are connected. Ground The main ground enters the ECM at P1-6 from the ground stud inside the ECM cabinet. The main ground leaves the ECM for a transfer switch or other remote battery charger at TB1-5 Start & Run Sequence 1.

Battery B+ applied to TB1-9 connects through F4 to S12 “RUN” through P4-6, and to K7 NO contacts through K6 NC contacts.

2.

When S12 is moved to “RUN” position, Battery B+ is applied to right side of K7 coil and K7 energizes. K7 NO contacts close and K2 and K3 coils energize.

3.

K3 NO contacts close and apply Battery B+ through F1 to the starter solenoid to crank the engine.

4.

K2 NO contacts close and apply Battery B+ through: F2 to engine terminal 26 to energize the fuel, ignition, and governor systems. F5 to P4-9 to provide power to the engine gauges and the hour meter.

5.

If the engine cranks for 15 seconds without starting, K12 will be energized and the K12 NC contacts will open to remove ground from the K3 coil. This allows the starter to rest for 15 seconds.

6.

Once the engine starts to accelerate and the DC alternator output reaches 18 Volts, the DC Starter Disconnect relay, K14, energizes. The K14 NO contacts close, opening the ground path for K3 and the starter is disengaged.

7.

Once the generator set reaches approximately 850 RPM, the AC Starter Disconnect signal from TB21-21 and TB21-32 reaches approximately 100 Volts. This signal energizes relay K10. The K10 NO contacts close supplying a ground to the RUN lamp on the front panel of the control through P3-5 and to the annunciator Run lamp through TB1-3.

Participant’s Guide

4-9

Lesson: Troubleshooting the DC Control

Remote

Integrated Generator Set Controls

P4

TB1 6

5 9 F5

Sw. B+ B+ In Starter B+ Out B+ Out (Shutdown)

10 9

DS4

8 7 DS9

DS3

K2

F2

K7

F3

DS8

5

Gnd when AC Start Disconnect is present

3

Off

7 S12

Run

K6 K6

K12 K10 K14

4

Ground Output

Remote

6

F4

K3

F1

DS1

To Gauges

K7

P3

K3

K10

B+ to A12 Lamps

5

A12 RUN Lamp

DS2

K2 K10

13

K14 DS6

K14

K10 DS5

P1

OH4Ć4

6

Ground Input

3

2

1

DC AC Start Disconnects

Slide 4-4 ECM Manual Operation Mode – Crank & Start

A11 K7 energizes when S12 is placed into the RUN position. Either A11 K10 or A11 K14 energizing will remove the ground from A11 K3 and remove the starter signal from A11 TB1-8. A11 K10 NO contacts to A11 TB1-3 will close when the AC start disconnect signal is received at A11 P1-1 and -2. 4-10

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the DC Control

ECM Automatic Operation Mode Checks B+ Battery B+ enters the ECM at TB1-9 and passes through F3 to the Remote Start Contacts in the transfer switch. Ground The main ground enters the ECM at P1-6 from the ground stud inside the ECM cabinet. The main ground leaves the ECM for a transfer switch or other remote battery charger at TB1-5 Start & Run Sequence 1.

Battery B+ applied to TB1-9 through F4 to K7 NO contacts through K6 NC contacts.

2.

For automatic operation, S12 must be left in the “Remote” position. This connects P4-5 to P4-7 and the right side of the K7 coil. When the Remote Start Contacts close, B+ is applied to TB1-6, P4-5, P4-7, and the right side of K7 coil energizing K7. K7 NO contacts close and K2 and K3 coils energize.

3.

K3 NO contacts close and apply Battery B+ through F1 to the starter solenoid to crank the engine.

4.

K2 NO contacts close and apply Battery B+ through: F2 to engine terminal 26 to energize the fuel, ignition, and governor systems. F5 to P4-9 to provide power to the engine gauges and the hour meter.

5.

If the engine cranks for 15 seconds without starting, K12 will be energized and the K12 NC contacts will open to remove ground from the K3 coil. This allows the starter to rest for 15 seconds.

6.

Once the engine starts to accelerate and the DC alternator output reaches 18 Volts, the DC Starter Disconnect relay, K14, energizes. The K14 NO contacts close, opening the ground path for K3 and the starter is disengaged.

7.

Once the generator set reaches approximately 850 RPM, the AC Starter Disconnect signal from TB21-21 and TB21-32 reaches approximately 100 Volts. This signal energizes relay K10. The K10 NO contacts close supplying a ground to the RUN lamp on the front panel of the control through P3-5 and to the annunciator Run lamp through TB1-3.

Participant’s Guide

4-11

Lesson: Troubleshooting the DC Control

Integrated Generator Set Controls

ECM Starter Disconnect Operation B+ Battery B+ enters the ECM at TB1-9 and passes through F3 to the Remote Start Contacts in the transfer switch. Ground The main ground enters the ECM at P1-6 from the ground stud inside the ECM cabinet. The main ground leaves the ECM for a transfer switch or other remote battery charger at TB1-5 Starter Disconnect Sequence The DC Starter Disconnect signal comes from the DC alternator. When this voltage reaches approximately 18 VDC (24 V systems), K14 energizes. The K14 NC contacts open and remove ground from K3 to de-energize K3. The AC Starter Disconnect signal comes from the main alternator stator output voltage connections at TB21-21 and TB21-32. When this voltage reaches approximately 85 VAC, K10 energizes. The K10 NC contacts open to remove ground from K3 to de-energize K3. The NO contacts close and apply a ground to TB1-3 to light the “Generator Running” lamp on the annunciator. If both DC and AC Starter Disconnect signals are present, the local run lamp on the front of the control box will light.

4-12

Participant’s Guide

Integrated Generator Set Controls

Remote

Lesson: Troubleshooting the DC Control

P4

TB1 6

5 9 F5

Sw. B+ B+ In Starter

10 9

DS4

8 7

B+ Out B+ Out (Shutdown) Ground Output Gnd when AC Start Disconnect is present

DS9

DS3

K2

F2

K7

F3

DS8

Off

7 S12

Run

K6 K6

K12 K10 K14

4 5

K7

P3

K3

K10 K10

13

B+ to A12 Lamps

5

A12 RUN Lamp

DS2

K2 3

Remote

6

F4

K3

F1

DS1

To Gauges

K14 DS6

K14

K10 DS5

P1

OH4Ć5

6

Ground Input

3

2

1

DC AC Start Disconnects

Slide 4-5 ECM Automatic Operation Mode – Remote Start Signal Input

A11 TB1 Terminal 7 feeds Battery B+ to a remote start contact. When the remote start contact closes, Battery B+ is fed to the Remote terminal of S12. With S12 in the Remote position, A11 K7 energizes when the remote start contacts close. Operation of the ECM is as above. Participant’s Guide

4-13

Lesson: Troubleshooting the DC Control

Remote

Integrated Generator Set Controls

P4

TB1 6

5 9 F5

Sw. B+ B+ In Starter

10 9

DS4

8 7

B+ Out B+ Out (Shutdown) Ground Output Gnd when AC Start Disconnect is present

DS9

DS3

K2

F2

K7

F3

DS8

Off

7 S12

Run

K6 K6

K12 K10 K14

4 5

K7

P3

K3

K10 K10

13

B+ to A12 Lamps

5

A12 RUN Lamp

DS2

K2 3

Remote

6

F4

K3

F1

DS1

To Gauges

K14 DS6

K14

K10 DS5

P1

OH4Ć6

6

Ground Input

3

2

1

DC AC Start Disconnects

Slide 4-6 ECM Automatic Operation Mode – DC Starter Disconnect

A11 K7 energizes when the remote start contacts close. Either A11 K10 or A11 K14 energizing will remove the ground from A11 K3 and remove the starter signal from A11 TB1-8. A11 K10 NO contacts to A11 TB1-3 will close when the AC start disconnect signal is received at A11 P1-1 and -2. 4-14

Participant’s Guide

Integrated Generator Set Controls

Remote

Lesson: Troubleshooting the DC Control

P4

TB1 6

5 9 F5

Sw. B+ B+ In Starter

10 9

DS4

8 7

B+ Out B+ Out (Shutdown) Ground Output Gnd when AC Start Disconnect is present

DS9

DS3

K2

F2

K7

F3

DS8

Off

7 S12

Run

K6 K6

K12 K10 K14

4 5

K7

P3

K3

K10 K10

13

B+ to A12 Lamps

5

A12 RUN Lamp

DS2

K2 3

Remote

6

F4

K3

F1

DS1

To Gauges

K14 DS6

K14

K10 DS5

P1

OH4Ć7

6

Ground Input

3

2

1

DC AC Start Disconnects

Slide 4-7 ECM Automatic Operation Mode – AC Starter Disconnect

A11 K7 energizes when the remote start contacts close. Either A11 K10 or A11 K14 energizing will remove the ground from A11 K3 and remove the starter signal from A11 TB1-8. A11 K10 NO contacts to A11 TB1-3 will close when the AC start disconnect signal is received at A11 P1-1 and -2. Participant’s Guide

4-15

Lesson: Troubleshooting the DC Control

Remote

Integrated Generator Set Controls

P4

TB1 6

5 9 F5

Sw. B+ B+ In Starter B+ Out B+ Out (Shutdown)

10 9

DS4

8 7 DS9

DS3

K2

F2

K7

F3

DS8

5

Gnd when AC Start Disconnect is present

3

Off

7 S12

Run

K6 K6

K12 K10 K14

4

Ground Output

Remote

6

F4

K3

F1

DS1

To Gauges

K7

P3

K3

K10

K14 DS6

K14

B+ to A12 Lamps

5

A12 RUN Lamp

DS2

K2 K10

13

K10 DS5

P1

OH4Ć8

6

Ground Input

3

2

1

DC AC Start Disconnects

Slide 4-8 ECM Diagram with Shutdown Fault

When a Shutdown input is received by the A11 ECM, the K6 relay is moved to the “set” position and mechanically latched into that position. This opens the K6 NC contacts leading to the K7 NO contacts and K2 and K3 deenergize. The K6 NO contacts close placing Battery B+ voltage onto A11 TB1 terminal 4. The G1 and G2 alternator outputs decrease below hold-in level so K10 and K14 will deenergize. 4-16

Participant’s Guide

Integrated Generator Set Controls

Remote

Lesson: Troubleshooting the DC Control

P4

TB1 6

5 9 F5

Sw. B+ B+ In Starter B+ Out B+ Out (Shutdown)

10 9

DS4

8 7 DS9

DS3

K2

F2

K7

F3

DS8

K6

4

Ground Output

5

Gnd when AC Start Disconnect is present

3

S12

K7

P3

K3

K10

K14 DS6

K14

Run

13

B+ to A12 Lamps

5

A12 RUN Lamp

DS2

K2 K10

Off

DS1 lit if B+ correct polarity DS8 lit if B+ incorrect polarity

K6

K12 K10 K14

Remote

6

F4

K3

F1

DS1

7

To Gauges

K10 DS5

P1

OH4Ć9

6

Ground Input

3

2

1

DC AC Start Disconnects

DS7 is connected to the W6 & W7 jumpers

Slide 4-9 ECM Overall Operation Diagram

Participant’s Guide

4-17

Lesson: Troubleshooting the DC Control

Integrated Generator Set Controls

ECM Overall Operation B+ Battery B+ enters the ECM at TB1-9 and passes through F3 to the Remote Start Contacts in the transfer switch. Ground The main ground enters the ECM at P1-6 from the ground stud inside the ECM cabinet. The main ground leaves the ECM for a transfer switch or other remote battery charger at TB1-5 Start & Run Sequence 1.

Battery B+ applied to TB1-9 through F4 to K7 NO contacts through K6 NC contacts.

2.

When K7 energizes, its NO contacts energize K2 (Switched B+) and K3 (Cranking).

3.

K3 sends B+ through F1 to the starter to crank the engine.

4.

K2 sends Switched B+ through F2 to engine terminal 26 for the engine fuel, ignition and governor systems, and through F5 to the engine gauges and meters.

5.

Once the engine starts to run on its own, one of the Starter Disconnect signals will de-energize K3 to disengage the starter from the flywheel. The DC Starter Disconnect signal comes from the DC alternator. When this voltage reaches approximately 18 VDC (24 V systems), K14 energizes. The K14 NC contacts open and remove ground from K3 to de-energize K3. The AC Starter Disconnect signal comes from the main alternator stator output voltage connections at TB21-21 and TB21-32. When this voltage reaches approximately 85 VAC, K10 energizes. The K10 NC contacts open to remove ground from K3 to de-energize K3. The NO contacts close and apply a ground to TB1-3 to light the “Generator Running” lamp on the annunciator. If both DC and AC Starter Disconnect signals are present, the local run lamp on the front of the control box will light.

6.

4-18

When B+ is removed from the K7 coil, or the K6 NC contacts open because of a shutdown signal, the K2 relay will de-energize. When the K2 NO contacts open, Switched B+ will be removed from engine terminal 26 and the engine will stop. Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the DC Control

DC Control Troubleshooting Quiz 1.

The Lamp Test switch does not light the A12 lamps. What could you check to find the problem?

2.

The generator set will start from the transfer switch, but not with S12 in the “RUN” position. What could you check to find the problem?

3.

The generator set will operate with S12 in the “RUN” position but not in “REMOTE.” What could you check to find the problem?

4.

The generator set starts and runs OK, but the “RUN” lamp on the control box does not light. What could you check to find the problem?

5.

The generator set does not crank at all. What could you check to find the problem?

6.

The generator set cranks but will not start and run. What could you check to find the problem?

7.

Where would you check to verify the AC Starter Disconnect is available?

8.

Where would you check to verify the genset was shut down on Emergency Stop after the Emergency Stop switch was pulled out.

9.

Which fuse would you check if the genset does not crank when S12 is in the “RUN” position?

10.

Which fuse would you check if the genset does not crank when S12 is in the “REMOTE” position?

Participant’s Guide

4-19

Lesson: Troubleshooting the DC Control

Integrated Generator Set Controls

This page intentionally left blank

4-20

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Simulator

The DC Control Simulator In this lesson you will construct a Detector-12 Control together, test inputs and outputs, and practice troubleshooting the Detector-12 Control.

Objectives After completing this lesson, you should be able to: • Replace an ECM board in a Detector Control on a generator set. • Replace a wiring harness in a Detector Control on a generator set. • Identify input and output signals, and their polarity, associated with the ECM. • Identify the position and function of ECM jumpers. • Describe the sequence of operation of the ECM.

Onan is a registered trademark of Onan Corporation.

Participant’s Guide

5-1

Lesson: DC Control Simulator

Integrated Generator Set Controls

Detector Control Simulator

F4

26

K3 F1 F2 K2 K7 TB1 VR 10 9 F3 1 K10 8 7 6 K6 5 4 K1 3 2 1 TB2 1 2 3 4 5 6 7 P1

OH5Ć1

S&TT 10/00

Slide 5-1 Detector Control Simulator

Use the following prints in your 960-0505 Service Manual to complete this exercise: • 612-6488 (pages 1 and 2) • INT-0192 (Operational diagram of the 12-light ECM) During this exercise, your team will be asked to go through the procedures necessary to replace a failed Detector-12 harness and a failed ECM board. These steps will help you prepare for the time when you have to do these same tasks because of a failure in the control box.

5-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Simulator

Detector 12 ECM U1

F4

U3

U5 P4

F

F5

F

1TB2

K2

K3 VR1

U2 K7

1

10

U4

K12

F3

9

K6

8

K10

K14

7

P

6

3

5 4 K1

3 2 1 P1

TB 2

1

2

3

4

5

6

7

8

9

10 11 12 13 14 15 16 P2

OH5Ć2

S&TT 10/00

Slide 5-2 Detector-12 ECM

Connecting The ECM Board To The Harness • Connect the wiring harness J3 to ECM P3. • Connect the wiring harness J4 to ECM P4. • According to the numbers printed on the wires, connect wiring harness leads to S11, S12, and DS11. 1.

Refer to the Wiring Diagram portion of your prints for terminal locations.

What print clearly shows the appropriate switch numbers? Wiring Diagram Number: 2.

Sheet

of 2.

Note: Six of the wires in this harness will not be used in this simulator. Four of the six are for meters. Normally the other two wires are not used and tied back into the harness.

What was the purpose of the other two wires? A11J4-1 A11J4-2

Participant’s Guide

5-3

Lesson: DC Control Simulator

Integrated Generator Set Controls

Connecting The ECM Board To The Harness What J1/P1 pin connects to the ground stud in the control box?

3.

Connect the BROWN ground wire from the ground screw to the appropriate terminal in the white plastic J1 connector shell, then connect J1 to P1.

Do not connect the wire directly to the P1 terminal on the ECM board. 4.

The red lamp that is mounted on the terminal 26 bracket has been provided to indicate when the control would be sending a Switched B+ output signal to terminal 26. The engine fuel solenoid, the governor and ignition coil are connected to terminal 26 on the generator set.

Where is TERMINAL 26 usually located on a generator set?

To which terminals on the ECM should the wires from Terminal 26 and the red lamp be connected? Terminal 26 Other red lamp wire 5.

Connect these two wires to the terminals on the ECM you indicated above.

6.

Place S12 in the STOP position.

7.

Connect the black lead from the power supply to the ground stud.

Where should the Positive power supply terminal connect on the ECM?

8.

5-4

Connect the striped lead with the insulated terminal from the power supply to the unfused B+ input terminal on TB1.

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Simulator

Detector Control Simulator

F4

26

K3 F1 F2 K2 K7 TB1 VR 10 9 F3 1 K10 8 7 6 K6 5 4 K1 3 2 1 TB2 1 2 3 4 5 6 7 P1

OH5Ć3

S&TT 10/00

Slide 5-3 Detector Control Simulator

Test for correct operation of the simulator. 9.

Plug the power supply into your extension cord. With S12 in the STOP position, the SWITCH OFF lamp should be flashing.

10.

Pressing S11 to LAMP TEST should illuminate all A12 lamps.

11.

Pressing S11 to PANEL LAMP should illuminate DS11.

What terminal on A11 TB1 connects to the starter solenoid?

12.

Connect your test lamp to the starter terminal on A11 TB1 and the ground stud. to monitor the voltage to the starter circuit.

13.

Place your finger lightly on the cover of K3 and put S12 in the RUN position. You should hear and feel K3 click about every 15 seconds for about 75 seconds. You should also see the test lamp alternately turn on and off at 15 second intervals.

Participant’s Guide

5-5

Lesson: DC Control Simulator

Integrated Generator Set Controls

What happens at the end of this 75 second period?

14.

Use your test lamp to check the COMMON ALARM output on TB1.

Is the COMMON ALARM terminal on A11 TB1 a Ground or B+ output?

15.

Reset the OVERCRANK fault by placing S12 in STOP and pressing S11 to RESET.

Why does the control fault out on OVERCRANK?

What input(s) are necessary to avoid faulting out on OVERCRANK?

Consult your wiring diagram to determine which pin number at J1 & P1 is for the DC Start Disconnect input. 16.

Simulate the DC Start Disconnect by connecting the RED wire from the appropriate pin on J1 to the Switched B+ terminal on TB1.

Which terminal on TB1 is Switched B+? TB117.

Connect one end of your simulated DC Start Disconnect wire to this terminal on TB1.

Which connector in J1 / P1 is the DC starter disconnect input? J1 / P1 18.

Remove J1 from P1 on the ECM. Place the other end of the simulated DC start disconnect wire into the appropriate hole in the J1 connector and reconnect J1 to P1.

19.

Place S12 in the RUN position while again feeling and listening for K3 to cycle. If you correctly connected the DC Start Disconnect signal, K3 should NOT cycle on and off as it did before.

20.

With the simulated DC start disconnect signal, the board should have immediately gone from the crank mode to the run mode.

5-6

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Simulator

Is the red lamp on the TERMINAL 26 bracket lit?

Yes / No

Is the green Local RUN lamp lit?

Yes / No

Why or why not? (Hint: See K10 on sheet #2 of print 612-6488) TB1-3 is output to a remote RUN lamp (usually on an annunciator). Is there an output at TB1-3?

Yes / No

What polarity?

Why?

Participant’s Guide

5-7

Lesson: DC Control Simulator

Integrated Generator Set Controls

Detector Control Simulator

F4

26

K3 F1 F2 K2 K7 TB1 VR 10 9 F3 1 K10 8 7 6 K6 5 4 K1 3 2 1 TB2 1 2 3 4 5 6 7 P1

OH5Ć4

S&TT 10/00

Slide 5-4 Detector Control Simulator

21.

You are about to connect AC Start Disconnect at J1 & P1. Place S12 in the STOP position.

What two J1/P1 pins are for AC Start Disconnect? and 22.

Remove J1 from P1 on the ECM. Install the pin connectors of the short AC power cord into the AC start disconnect pins in J1 and reconnect J1 to P1 on the ECM.

23.

Move the wire attached to the red lamp from TB1-5 to TB1-3 (remote RUN). This will allow the red lamp to simulate the RUN lamp on an annunciator. It will still have Switched B+ on one side (T26) but the other signal will depend on the AC start disconnect input to the ECM.

24.

Please have your instructor check your work before proceeding. _____________________________ Instructor’s okay

5-8

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Simulator

Detector Control Simulator

F4

26

K3 F1 F2 K2 K7 TB1 VR 10 9 F3 1 K10 8 7 6 K6 5 4 K1 3 2 1 TB2 1 2 3 4 5 6 7 P1

OH5Ć5

S&TT 10/00

Slide 5-5 Detector Control Simulator

25.

Move S12 to the RUN position and then connect the short AC power cord to the extension cord.

Does the green Local RUN lamp light now?

Yes / No

Why?

Is there an output at TB1-3?

Yes / No

What polarity?

Why?

26.

Remove the simulated DC Start Disconnect signal by disconnecting the RED wire from TB1-10, but leave the AC Start Disconnect signal connected.

Participant’s Guide

5-9

Lesson: DC Control Simulator

Does the green RUN lamp on DS12 remain on?

Integrated Generator Set Controls

Yes / No

Why?

Is there an output at TB1-3?

Yes / No

What polarity?

Why?

What can you conclude about the relationship between the AC Start Disconnect Input and the Remote RUN Lamp?

What can you conclude about the relationship between the AC and DC Start Disconnect inputs and the Local RUN Lamp?

27.

Disconnect the AC start Disconnect cord from the extension cord.

28.

Move S12 to the STOP position and reconnect the RED (simulated DC start disconnect signal) wire to A11 TB1-10.

29.

Move the red lamp wire from TB1-3 back to TB1-5.

5-10

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Simulator

Detector Control Simulator

F4

26

K3 F1 F2 K2 K7 TB1 VR 10 9 F3 1 K10 8 7 6 K6 5 4 K1 3 2 1 TB2 1 2 3 4 5 6 7 P1

OH5Ć6

S&TT 10/00

Slide 5-6 Detector Control Simulator

ALARMS & FAULTS What pin at J2/P2 is for Pre-LOP input?

30.

Move S12 to the RUN position. After approximately ten seconds you will hear A11K1 energize. This is the Oil Pressure Time Delay (OPTD) relay. After A11K1 energizes, the ECM can sense oil pressure, water temperature, and timed customer fault (FLT) inputs.

31.

Place the appropriate PRE-LOP input signal at the proper P2 pin.

Does the Pre-LOP lamp in the A12 lamp assembly light?

Yes / No

Is there a time delay before anything happens?

Yes / No

32.

Do not reset the control yet.

What pin at J2/P2 is for LOP shutdown input?

Participant’s Guide

5-11

Lesson: DC Control Simulator

33.

Integrated Generator Set Controls

Momentarily place the LOP Fault input at P2.

Does the LOP lamp in the A12 lamp assembly light>

Yes / No

Is there a time delay before anything happens?

Yes / No

What polarity is the Common Alarm output at A11 TB1-4?

Why is this output here now?

Did the RUN lamp at terminal 26 go out?

Yes / No

Why or why not?

34.

Reset the control and check at least one other alarm and fault input at P2.

35.

Next you will check the customer fault inputs and outputs at TB2-1 through TB2-4.

What would you connect to these terminals?

What polarity of signal is required as an input for FLT2 and FLT1 to operate?

What polarity of signal is the output from FLT2 and FLT1 (TB2-2 or TB2-4)?

36.

Reset any remaining alarms or faults. Place the proper input signal at TB2-1 and move S12 to the RUN position.

Is there a time delay before FLT2 operates?

Yes / No

Is FLT2 a Pre-Alarm or a Shutdown?

37.

Reset the control. Place the proper input signal at TB2-3 and move S12 to the RUN position

Is there a time delay before FLT1 operates? 5-12

Yes / No Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Simulator

Is FLT2 a Pre-Alarm or a Shutdown?

What jumpers on the A11 ECM change FLT2 and FLT1 to Pre-Alarm or Shutdown? FLT2 FLT1 Do these jumpers have control when the genset is not operating? 38.

Yes / No

On the new ECM (with the white A11K2 and A11K3 relays) some of the other jumpers are also moveable without using a soldering iron.

Which jumpers are moveable by hand?

What is the function of W6?

What is the function of W7?

39.

Place W6 or W7 in position “B” and test the Pre-LOP or Pre-HET functions again.

What happened this time?

Why?

What is the function of W8 and W9?

40.

Move S12 to the STOP position and reset the control.

41.

Move W2 to the “B” position and W8 to the “A” position. With S12 in the REMOTE position, place a ground signal on TB2-1

What happened?

Participant’s Guide

5-13

Lesson: DC Control Simulator

Integrated Generator Set Controls

Why?

When would this be useful?

5-14

Participant’s Guide

Integrated Generator Set Controls

Lesson: DC Control Simulator

Detector Control Simulator

F4

26

K3 F1 F2 K2 K7 TB1 VR 10 9 F3 1 K10 8 7 6 K6 5 4 K1 3 2 1 TB2 1 2 3 4 5 6 7 P1

OH5Ć7

S&TT 10/00

Slide 5-7 Detector Control Simulator

Disconnecting The Simulator 42.

Please connect all moveable jumpers to the positions shown below so the next class can get the same training you did. W1 ⇒ B W6 ⇒ A W8 ⇒ B

43.

W2 ⇒ D W7 ⇒ A W9 ⇒ B

Disconnect all wires except those listed below.

DO NOT disconnect the following leads: – The lead from the ground stud to the door. – Ground wire on door hinge which was connected to S11-2. – The two wires at the Terminal 26 screw. – Harness between A12 lamp assembly and P3. – A11P4 and the J4 harness to the door. 44.

Disconnect J1 from P1 and use the pin removal tool to carefully remove all wires from J1.

Participant’s Guide

5-15

Lesson: DC Control Simulator

Integrated Generator Set Controls

45.

Do not use force to separate the pins from the J1 8-pin housing. If you need instruction on the use of the pin tool, please ask. It is very easy to destroy the pins.

46.

If you destroy a pin, please ask your instructor for a replacement pin and crimp tool to make the repair to the simulator.

47.

Connect J1 to P1.

48.

Place all of the following loose parts in the simulator: – Short AC Start Disconnect cord – AC extension cord – Power supply with leads wrapped up – Pin removal tool – All loose leads and jumper wires – Test Light – Screwdriver

49.

Ask your Instructor to verify proper disassembly, and where the simulator is to be placed for storage.

5-16

Participant’s Guide

Integrated Generator Set Controls

Lesson: The DC Control Auxiliary Relay Board

The DC Control Auxiliary Relay Board (ARB) This lesson presents an overview of the operation and troubleshooting of the Auxiliary Relay Board (ARB) used with the A11 ECM.

Objectives After completing this lesson, you should be able to: • Identify input and output signals, and their polarity, associated with the Auxiliary Relay Board. • Identify the position of jumpers used with the K1, K2 and K3 relays when using the relay as a Run relay, Common Alarm relay, or an Isolated relay. • Describe the sequence of operation of the K1, K2 or K3 relays when they are used as a Run relay, Common Alarm relay and an Isolated relay. • Identify input and output signals for the optional relays and terminal boards on the ARB.

Cummins is a registered trademark of Cummins, Inc.

Participant’s Guide

6-1

Lesson: The DC Control Auxiliary Relay Board

Integrated Generator Set Controls

JUMPERS

RUN RELAY MODULE(S)

K1

J1, J2 WIRE HARNESS PLUG CONNECTIONS FROM A11

OH6Ć1

K2

JUMPERS

K3

TB6, TB7 AND RELAYS K4 THROUGH K15 ARE OPTIONAL

S&TT 10/00

Slide 7-1 AUXILIARY RELAY BOARD (ARB)

6-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: The DC Control Auxiliary Relay Board

Optional Auxiliary Relay Board (A28) The following describes the design/functional criteria for the auxiliary relay board (ARB) with a Detector-7 or -12 Genset control. When provided, the board is mounted on the rear wall of the control box as shown in slide 1. There are two versions of the ARB; with and without the set of 12 Fault relays. Terminal Blocks: • TB1 – ARB TB1 and engine monitor TB1 are identically numbered and provide the same remote control connection points. Note that additional terminals are provided for terminals 5, 7, and 10 of ARB TB1. • TB2 through TB5 – Connection points for relays K1 through K3. TB2 provides the N/O and N/C connections (three form ‘C’ contacts for each relay). TB3 through TB5 provide the common connection points (TB3 for K1, TB4 for K2 and TB5 for K3). • TB6 and TB7 – Connection points for fault relays K4 through K15. Three terminals are provided for each relay, which are labeled COM, N/C, N/O. Plug-In Relays (K1, K2, K3): • The ARB can be equipped with up to three 3-pole, double-throw relays. These relays (K1, K2, K3) are field changeable plug-in relays for easy field addition and replacement. • Each relay can be operated as a RUN Relay, COMMON ALARM Relay, or ISOLATED COIL Relay with the changing of a jumper. The relay contact ratings are: • 10 amps at 28 VDC or 120 VAC, 80% PF • 6 amps at 240 VAC, 80% PF • 3 amps at 480 VAC, 80% PF Fault Relays (K4 through K15) • These optional relay modules are used to operate a remote alarm annunciator that has an independent power source. This allows the use of either AC or DC for alarm drives. The relays are energized through the latching relays on the engine monitor and provided N/O and N/C contacts for each external alarm connection. • The 12 relays with form ‘C’ contacts are rated at 10 Amp, 120 VAC or 10 Amp. 30 VDC Participant’s Guide

6-3

Lesson: The DC Control Auxiliary Relay Board

Integrated Generator Set Controls

K1 Relay Connections W1

Common Alarm B+

B

W11

A 11

A

K1.1 11 10

B

10

SW B+ 1

C TB3

5

B 1

A 1

Ground 11

K2.1 11 10

10

1 TB4

B 1

11 5

A 1

OH6Ć2

K3.1 11 10

10

1 TB5

B 1

5 A 1 S&TT 10/00

Slide 7-2 Portion of ARB schematic diagram showing K1 circuits

Jumper settings for K1 Relay Operation W1

W11

K1 Energizes when:

A

B

Genset cranks or runs.

A

A

Genset cranks or runs and an isolated ground is applied to TB3-5.

B

B

Genset has a shutdown fault.

B

A

Genset has a shutdown fault and an isolated ground is applied to TB3-5.

C

B

Isolated B+ is applied to TB3-1.

C

A

Isolated B+ is applied to TB3-1 and an isolated ground is applied to TB3-5.

W2 / W12 perform the same functions for K2 W3 / W13 perform the same functions for K3 K1 is factory set as a “RUN” relay, K2 as a “Common Alarm” relay, and K3 as an “Isolated” relay. 6-4

Participant’s Guide

Integrated Generator Set Controls

Lesson: The DC Control Auxiliary Relay Board

Jumper Positions for Plug-In Relays: Jumpers W1, W2 and W3 perform the same functions for their respective relays. • W1 for relay K1, W2 for relay K2, and W3 for relay K3. • These jumpers control how B+ is connected to the relay coil via TB3-1, TB4-1 or TB5-1. These jumpers can be located in any of 3 positions (A, B, C) independently of each other. • Jumper Position A (Run) The associated relay operates as a Run relay, energizing when SW B+ is applied from the engine monitor. • Jumper Position B (Common Alarm) The associated relay operates as a Common Alarm relay. The relay energizes any time there is an engine shutdown. This signal is provided from the engine. • Jumper Position C (Isolated) The associated relay operates as an Isolated relay. The relay coil is energized by a customer applied B+ signal through the terminal block; TB3-1 for relay K1, TB4-1 for relay K2, and TB5-1 for relay K3. Jumpers W11, W12, and W13 perform the same functions for their respective relays. • W11 for relay K1, W12 for relay K2, and W13 for relay K3. • These jumpers control how GND is connected to the relay coil via TB3-5, TB4-5 or TB5-5. These jumpers can be located in two different positions (A, B) independently of each other. • Jumper Position A The relay operates isolated from the board. The customer provides the circuit completion through terminal block; TB3-5 for relay K1, TB4-5 for relay K2, and TB5-5 for relay K3. The customer can operate the relay with switched ground logic or use this relay in the middle of more complex logic circuits if needed. • Jumper Position B The relays operate with the coils connected to ground through the board connections. The coil will require a B+ signal to energize with the jumper in this position.

Participant’s Guide

6-5

Lesson: The DC Control Auxiliary Relay Board

Integrated Generator Set Controls

Auxiliary Relay Board Quiz Select the best answer for each question. 1.

Which jumpers are used with the K2 relay? A. W1, W11 B. W2, W12 C. W3, W13 D. W2, W22

2.

Where would you place the W1 jumper to have the K1 relay operate when there is a shutdown? A. A B. B C. C D. D

3.

Where would you place jumper W11 to use a ground input from a louver limit switch to light a lamp when the genset is running and the louvers are open? A. A B. B C. C D. D

4.

When using K3 as an isolated relay, where do the coil wires connect to their signals? A. TB2 B. TB3 C. TB4 D. TB5

5.

TB1 on the ARB connects to ______ on the ECM. A. P1 B. P2 C. TB1 D. TB2

6.

TB6 on the ARB provides connection points for relays A. LOP and LET. B. HET and OC. C. PRELOP and SW OFF. D. FLT1 and OS.

6-6

Participant’s Guide

Integrated Generator Set Controls

Lesson: AC Control Inputs and Outputs

AC Control Inputs and Outputs This lesson presents an overview of the input and output signals associated with the AC Control section of an Integrated generator set.

Objectives After completing this lesson, you should be able to: • Identify integrated generator set AC Control components. • Describe the sequence of operation of the integrated generator set AC Control. • Identify and locate jumpers used on the different automatic voltage regulators (AVRs). • Identify input and output signals for the different AVRs used with Integrated generator sets. • Develop a troubleshooting aid showing input and output voltages from no-load to 100% load on the different AVRs used with Integrated gensets.

Cummins is a registered trademark of Cummins, Inc.

Participant’s Guide

7-1

Lesson: AC Control Inputs and Outputs

Integrated Generator Set Controls

AC Control Block Diagram

Rotating Diodes

Exciter Rotor

Main Rotor

Main Stator

SENSING

CONTROL

Voltage Regulator OUTPUT

Exciter Stator

L1 L3

L0

L2 OH7Ć1

S&TT 10/00

Slide 7-1 Block diagram of a typical AC Control

This diagram shows the two main types of hardware used in Cummins/Onan generator set AC Controls. The top (dashed) box contains all the hardware used in AC Controls which moves. These pieces are connected to the engine crankshaft with a flexible connection which helps prevent vibration caused by unbalance and alignment from affecting engine operation. The bottom box contains all the hardware used in AC Controls which is stationary. These pieces are either built into the stator housing or are in the Control Box. The Voltage Regulator performs three separate functions: • SENSING

Determines if the input voltage is too low, just right, or too high.

• CONTROL

Tells the Output section what to do to get the input voltage to the proper level.

• OUTPUT

Increases or decreases the current through the Exciter Stator to increase or decrease the voltage input to the AVR.

7-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: AC Control Inputs and Outputs

AC Control Inputs & Outputs

Rotating Diodes

Exciter Rotor

Main Rotor (–)

Exciter Stator

AVR

(+)

Main Stator

XX (–)

Excitation

Reference Voltage

X (+)

L1 L3

L0

CB21

L2 Regulator Power (Drive Voltage)

OH7Ć2

S&TT 10/00

Slide 7-2 Each part in the AC Control System has an input (or inputs) and an output.

Part Name

Input

Output

• AVR

Reference Voltage Regulator Drive Voltage

Excitation Voltage

• Exciter Stator

Excitation Voltage

Magnetic Flux

• Exciter Rotor

Magnetic Flux

3-Phase AC Voltage

• Rotating Diodes

3-Phase AC Voltage

DC Voltage

• Main Rotor

DC Voltage

Magnetic Flux

• Main Stator

Magnetic Flux

1-Phase AC or 3-Phase AC Voltage

Participant’s Guide

7-3

Lesson: AC Control Inputs and Outputs

EXCITER ROTOR

Integrated Generator Set Controls

ROTATING RECTIFIERS MAIN ROTOR

EXCITER STATOR

MAIN STATOR

8 7

Sensing and Drive Input Voltage TB21 (VR21) 32 31

VRAS-2 AVR

25 24 7 8

23

1 2 34 5 6

7 8

9 10

22 21

AC Start Disconnect

Field Circuit Breaker CB21

OH7Ć3

Voltage Trimmer R21 (NOTE 3) S&TT 10/00

Slide 7-3 Onan 300-2880 AVR connection diagram

NOTES: 1. 2. 3. 4. 5.

7-4

7 and 8 are sensing leads wound into the generator as sensing leads. Unless the genset is used in a paralleling situation, there will be a jumper between terminals 3 and 4 on the VR21 terminal block. There must be a fixed 5kΩ resistor between VR21-7 and VR21-8 when R21 is not used. This type of Voltage Regulator puts out 120 VAC from terminals 1 and 5 for the AC Start Disconnect signal for the A11 DC Control board. All integrated genset AVRs send an AC Start Disconnect signal to the A11 ECM from TB21-21 and TB21-32.

Participant’s Guide

Integrated Generator Set Controls

EXCITER ROTOR

Lesson: AC Control Inputs and Outputs

ROTATING RECTIFIERS MAIN ROTOR

OUTPUT VOLTAGE SENSING LEADS (NOTE 2)

EXCITER STATOR

MAIN STATOR

8 7 6

(VR21)

TB21 32 31

SX-440 or SX-460 VOLTAGE REGULATOR

K1 K2 P2 P3 P4 S2 S1 A2 A1 XX XX X 8 7 6 3 2 1 AUXILIARY TERMINAL BOARD

5 6

26 25

Sensing Drive 1 2 3 X XX

P3 P2 K1 K2

24 7 8

23 22 21

AC Start Disconect

Field Circuit Breaker CB21

Voltage Trimmer R21 (NOTE 3) OH7Ć4

S&TT 10/00

Slide 7-4 Non-PMG Newage AVR connection diagram

NOTES: 1. 2. 3. 4.

Connect like numbered terminals on Auxiliary Terminal Board and AVR. See the appropriate reconnection diagram for placement of sensing leads 6, 7, and 8 on the generator reconnection block. There must be a jumper between TB21–21 and VR21–1 when R21 is not used. Sensing wires 7 and 8 connect to terminals 2 and 3 on the SX-440 AVR.

Participant’s Guide

7-5

Lesson: AC Control Inputs and Outputs

Integrated Generator Set Controls

ROTATING RECTIFIERS

EXCITER ROTOR

MAIN ROTOR

PMG ROTOR EXCITER STATOR

N S

MAIN STATOR

PMG STATOR

8 7 6

AC Start Disconnect TB21

ISOLATION TRANSFORMER (NOTE 3) INPUT

OUTPUT

8 7 6 –

8 7 6 –

K1 K2 P2 P3 P4 S2 S1 A2 A1 XX XX X 8 7 6 3 2 1 AUXILIARY TERMINAL BOARD

32 31

5 6

26 25

2

(VR21)

1 8

24 7

7

23

6

22

X

21

XX

Sensing

8

P4 Voltage Trimmer R21 (NOTE 4) Field Circuit Breaker CB21

OH7Ć5

P3 P2 K1

Drive MX-321 VOLTAGE REGULATOR

E0 E1

Over Voltage Sensing Input

K2

S&TT 10/00

Slide 7-5 PMG AVR connection diagram

NOTES: 1. Connect like numbered terminals on auxiliary terminal board and voltage regulator. 2. See the appropriate reconnection diagram for connecting sensing leads 6, 7, and 8. 3. When the generator is connected for single-phase output, voltage regulator terminal 6 is not connected to the isolation transformer but is jumpered to voltage regulator terminal 8. 4. There must be a jumper between voltage regulator terminals 1 and 2 when voltage trimmer R21 is not used. 5. The resistor between terminals 26 and 32 of TB21 reduces the AC Start Disconnect signal to 120 VAC maximum for the A11 ECM. 7-6

Participant’s Guide

Integrated Generator Set Controls

Lesson: AC Control Inputs and Outputs

TB21 Connections From Auxiliary terminal block or generator sensing leads

TB21 32

(AC Start Disconnect) To ECM

31

Resistor only used with Newage AVRs Sensing Lead 5

30 29 28 27

Sensing Lead 6 Sensing Lead 4 (Metering only) Sensing Lead 7

26 25

To AVR

24 23 22

To AVR To AVR

21 OH7Ć6

Sensing Lead 8

S&TT 10/00

Slide 7-6 AC Control Inputs and Outputs — TB21 Connections

TB21 INTEGRATED GENSET INPUTS When the generator is connected in a WYE or STAR configuration: Sensing leads 4 and 5 will be connected to the L0 or Neutral terminal Sensing lead 6 will be connected to the midpoint of Phase C (L3) Sensing lead 7 will be connected to the midpoint of Phase A (L1) Sensing lead 8 will be connected to the midpoint of Phase B (L2) TB21 INTEGRATED GENSET OUTPUTS Reference Voltage for all Integrated Genset AVRs comes from TB21. • Single-phase sensing AVRs (VRAS-2 and SX440) sense only phases A and B. Their Reference voltage comes from TB21-22 and TB21-23. • The MX321 is a three-phase sensing AVR, and it gets its reference voltage from TB21 terminals 22, 23 and 25. • The AC start disconnect for the A11 ECM comes from TB21 terminals 21 (jumpered to terminal 22) and 32. The resistor between TB21-26 and -32 drops this voltage to a 90 to 120 VAC range to prevent burning out A11 K10. Participant’s Guide

7-7

Lesson: AC Control Inputs and Outputs

Integrated Generator Set Controls

VRAS-2 Inputs / Outputs

300-2880

S1 S2 S3

Volts R-32

1

2

3

4

OH7Ć7

5

6

Volts/Hz (sealed) 7

8

9 10

R-34

R21

S&TT 10/00

Slide 7-7 AC Control Inputs and Outputs — 300-2880 and 300-2977

The 300-2880 AVR is used with 20–350 kW Onan generators including all “A” sets and the “A– replacement” sets. The 300-2977 AVR is used with Onan generators from 325-750 kW. 300-2880 INPUTS 208 - 240 VAC input (common to Reference & Drive Voltages) Drive Voltage return Reference Voltage return Unless installed in a paralleling system, terminals 3 & 4 will be jumpered together. 300-2880 OUTPUTS 120 VAC output for AC Start Disconnect 120 VAC output for AC Start Disconnect Excitation + (F1) Excitation – (F2)

7-8

Participant’s Guide

Integrated Generator Set Controls

Lesson: AC Control Inputs and Outputs

SX-440 Inputs / Outputs OVER 550 kW 90 – 550 kW UNDER 90 kW A B C

60 C 50

STABILITY

Optimum Response Selection 8 7 6 5 4 3 2 1 S2 S1 A2 A1

UFRO LED Indicator

VOLTS

DROOP

BLUE CAP.

V/TRIM

É É É

305-0824

R21 OH7Ć8

S&TT 10/00

Slide 7-8 AC Control Inputs and Outputs — SX440 (305-0624) or SX-460

The SX-440 AVR is used with Newage UC-type generators from 20-175 kW. SX440 INPUTS Reference Voltage (208–240 VAC) Reference Voltage (208–240 VAC) AVR Drive Voltage (208–240 VAC) AVR Drive Voltage (208–240 VAC) S1 - S2 Cross-Current CT inputs for paralleling A1- A2 VAR/PF module inputs for paralleling to a utility SX440 OUTPUTS Excitation + Excitation –

NOTE:

On all Newage AVRs the K1 and K2 terminals must be connected by a jumper or a circuit breaker to get excitation output from the AVR.

Participant’s Guide

7-9

Lesson: AC Control Inputs and Outputs

Integrated Generator Set Controls

MX-321 Inputs / Outputs R21 P4 XX X 6

K1 K2 P2 P3

FREQUENCY SELECTION

7 8 1 2

NO LINK 6P - 50 6P - 60 4P - 50 4P - 60

UNDER FREQUENCY

321

VOLTS I/LIMIT

RMS

DIP

DWELL STABILITY OPTIMUM RESPONSE SELECTION

OVER/V E0 E1 B0 B1

FRAME 1, 2 FRAME 3, 4, 5 FRAME 6, 7

EXC TRIP CBA

U V W DROOPV/TRIM S1 S2 S1 S2 S1 S2 A1 A2

305-0823

OH7Ć9

S&TT 10/00

Slide 7-9 AC Control Inputs and Outputs — MX321 (305-0623)

The MX-321 AVR is used with Newage HC-type generators from 200-1500 kW. MX321 INPUTS Reference Voltage (Phases A, B & C) Regulator Drive Voltage (3-Phase input) Overvoltage Sensing input WS1-WS2 A1 - A2

Cross-Current CT inputs for paralleling VAR/PF module inputs for paralleling to a utility

MX321 OUTPUTS Excitation + Excitation – B0 - B1 7-10

60 VDC pulse to shunt trip exciter breaker with trip feature. Participant’s Guide

Integrated Generator Set Controls

Lesson: AC Control Inputs and Outputs

AVR Load Chart

300-2880

S1 S2 S3

Volts R-32

R-34 Do Not adjust this potentiometer.

1

2

3

4

5

6

7

8

9 10

OH7Ć10

S&TT 10/00

Slide 7-10 AVR Inputs and Outputs — VRAS-2

Using the generator set and load bank in the shop, complete the worksheet for this regulator. Reference and Drive Voltage Pins Load

Excitation Voltage (+)

Frequency

(–)

No Load 20% 40% 60% 80% 100%

Participant’s Guide

7-11

Lesson: AC Control Inputs and Outputs

Integrated Generator Set Controls

AVR Load Chart A B C

60 C 50

STABILITY

UFRO

Optimum Response Selection 8 7 6 5 4 3 2 1 S2 S1 A2 A1

LED Indicator

VOLTS

ÉÉ ÉÉ ÉÉ

BLUE CAP.

DROOP V/TRIM

R21

Do Not Adjust potentiometers marked like this.

OH7Ć11

S&TT 10/00

Slide 7-11 AVR Inputs and Outputs — SX-440 or SX-460

Using the generator set and load bank in the shop, complete the worksheet for this regulator. Reference Voltage Pins Load

Drive (Power) Voltage

Excitation Voltage (+)

Frequency

(–)

No Load 20% 40% 60% 80% 100%

7-12

Participant’s Guide

Integrated Generator Set Controls

Lesson: AC Control Inputs and Outputs

AVR Load Chart R21 P4 XX X 6

K1 K2 P2 P3

7 8 1 2

FREQUENCY NO LINK 6P - 50 SELECTION 6P - 60

VOLTS

4P - 50 4P - 60

321

UNDER FREQUENCY DIP

DWELL STABILITY OPTIMUM RESPONSE SELECTION

550 kW

U V W E0 E1 B0 B1 OH7Ć12

S1 S2 S1 S2 S1 S2 A1 A2

CBA

Do Not Adjust potentiometers marked like this.

S&TT 10/00

Slide 7-12 AVR Inputs and Outputs — MX-321 Check PMG input at PMG connector, check sense voltage input at TB21

Using the generator set and load bank in the shop, complete the worksheet for this regulator. Reference Voltage Pins Load

TB21– TB21–

Drive (Power) Voltage P

P

Excitation Voltage (+)

Frequency

(–)

No Load 20% 40% 60% 80% 100%

Participant’s Guide

7-13

Lesson: AC Control Inputs and Outputs

Integrated Generator Set Controls

This page intentionally left blank

7-14

Participant’s Guide

Integrated Generator Set Controls

Lesson: Automatic Voltage Regulator Adjustments

Automatic Voltage Regulator Adjustments This lesson presents an overview of adjusting the potentiometers and jumpers on the Onan and Newage Automatic Voltage Regulator (AVR) boards.

Objectives After completing this lesson, you should be able to: • Identify Cummins/Onan Automatic Voltage Regulator (AVR) adjustments. • Identify function of the adjustments on Cummins/Onan AVRs. • Properly adjust a VRAS-2 AVR for a specific generator set. • Properly adjust an SX-440 AVR for a specific generator set. • Properly adjust an MX-321 AVR for a specific generator set.

Cummins is a registered trademark of Cummins, Inc. Onan is a registered trademark of Onan Corporation.

Participant’s Guide

8-1

Lesson: Automatic Voltage Regulator Adjustments

Integrated Generator Set Controls

VRAS-2 AVR Switches & Pots

S1 or S3 1

2

3

4

On Off

S2 S1

2 S2

S3

Volts R-32

1

2

OH8Ć1

3

4

5

6

Volts/Hz (sealed) 7

8

9 10

R-34 S&TT 10/00

R21

Slide 8-1 AC Control Inputs and Outputs — 300-2880 and 300-2977

The 300-2880 AVR is used with 20–350 kW Onan generators including all “A” sets and the “A– replacement” sets; the 300-2977 AVR is used with 325–750 kW Onan generators. 300-2880 and 300-2977 Adjustments R34 (Volts/Hz) Adjusts the rate at which the AVR will drop or increase output voltage after a load application or removal. This pot is adjusted on a computerized test bench, not in the field. R32 (Volts) Adjusts the AVR to a specific Reference Voltage with a particular load. This pot is adjusted after the front-panel voltage adjust pot (R21) is set to its midpoint. Jumper between terminals 3 and 4is replaced with cross-current compensation circuit in paralleling installations. S1, S2 and S3 These are set according to the Service Manual for the specific generator set.

8-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: Automatic Voltage Regulator Adjustments

VRAS-2 Operating Modes 100 95 90 80 70 60 50 0

0

OH8Ć2

50

80

85

90

95

Percent of operating RPM

100 S&TT 10/00

Slide 8-2 Onan VRAS-2 Operating Modes Frequency Sensitive Soft AVR (TMA)

Torque Matching Medium AVR (TMB)

Non-Frequency Sensitive Hard AVR (TMC)

By moving the S1, S2 and S3 switches on the Onan VRAS-2 AVRs (300-2880 and 300-2977) the technician can adjust the operation of the AVR for different types of loads. The settings of S1, S2 and S3 are shown in the applicable Service Manual. • The TMB setting is the factory standard for all Onan generator sets. This is a compromise setting that makes the generator/regulator operate in a Semi-Frequency Sensitive mode. As the frequency drops from 100% to 90%, the voltage drops 1% for each 1% of frequency drop. When the frequency goes below 90% of nominal, the rate of decrease of the voltage doubles. • The TMA setting is the Frequency-Sensitive mode of operation. The voltage drops off at 2% for each 1% decrease in the frequency. This setting sacrifices voltage to keep the frequency as high as possible. This setting is recommended for heavy motor loads. • The TMC setting is a Non-Frequency Sensitive setting that keeps the voltage constant until the frequency drops below 90% of nominal. Then the voltage drops at 2% for each 1% of frequency drop. Participant’s Guide

8-3

Lesson: Automatic Voltage Regulator Adjustments

Integrated Generator Set Controls

SX-440 AVR Jumpers & Pots OVER 550 kW 90 – 550 kW UNDER 90 kW 60 C 50

A B C

STABILITY

Optimum Response Selection

UFRO LED Indicator

Reference Voltage jumpers set for AC reference input. VOLTS

Reference Voltage jumpers set for DC reference input. S2 S1 A2 A1

DROOP V/TRIM 1 2 3 X XX P4 P3 P2 K1 K2

R21 OH8Ć3

S&TT 10/00

Slide 8-3 AC Control Inputs and Outputs — SX440 (305-0624)

SX440 Adjustments Stability Adjusts the amount of damping in the AVR regulation circuit. The higher the damping effect of this circuit, the slower the voltage changes. Volts Adjusts the AVR to a specific Reference Voltage with a particular load. This pot is adjusted after the Optimum Response Selection jumper is connected for a specific alternator. V/Trim Adjusts the amount of control an external option, connected at A1/A1, has on the AVR. Droop Adjusts the amount of cross-current compensation the AVR produces when a paralleling CT is connected to S1/S2. UFRO Adjusts the break point frequency for 100% 0.8 power factor load acceptance. This is the frequency at which the generator set output voltage starts to drop. 8-4

Participant’s Guide

Integrated Generator Set Controls

Lesson: Automatic Voltage Regulator Adjustments

Newage UFRO setting 100 95 90 80 70 60 50 0

0

45

OH8Ć4

50

54

58

Operating Frequency

59.5

60 S&TT 10/00

Slide 8-4 UFRO setting for Newage AVRs

The Newage AVRs do not have switches to change the AVR operating characteristics like the Onan AVRs. The Newage AVRs use the UnderFrequency Roll-Off (UFRO) potentiometer to set the frequency at which voltage starts to decrease. To set the UFRO potentiometer, the technician has to actually change the generator set output frequency to the desire roll-off point and then set the AVR to that point. • The technician first determines the type of load and the frequency at which the genset output voltage should start to drop off. Factory setting for 200 kW and up sets is 59.5 Hz. UPS loads may require the UFRO point to be lowered to 54 Hz to keep the voltage as steady as possible when the UPS is trying to acquire the genset as a source. • The technician makes sure that the load is disconnected from the genset and adjusts the governor to the proper frequency point. • When the generator set has stabilized at the desired frequency, the technician turns the UFRO potentiometer until the UFRO LED is off, then back until the UFRO LED just lights. • The UFRO LED should be lit when the genset is at the desired roll-off frequency. • After the AVR is set, the technician resets the governor to the proper operating frequency. 60 Hz for isochronous operation, 61.8 Hz for 3% droop, 63 Hz for 5% droop. Participant’s Guide

8-5

Lesson: Automatic Voltage Regulator Adjustments

Integrated Generator Set Controls

MX-321 Jumpers and Pots R21 K1 K2 P2 P3

P4 XX X 6

7 8 1 2

FREQUENCY NO LINK 6P - 50 SELECTION 6P - 60 4P - 50 4P - 60 UNDER FREQUENCY 321 ROLL OFF (UFRO) RMS DIP

VOLTS

I/LIMIT

DWELL STABILITY OPTIMUM RESPONSE SELECTION

Under 90 kW 90–550 kW Over 550 kW U V W DROOP V/TRIM

EXC TRIP

OVER/V E0 E1 B0 B1

CBA

OH8Ć5

S1 S2 S1 S2 S1 S2 A1 A2 S&TT 10/00

Slide 8-5 AC Control Inputs and Outputs — MX321 (305-0623)

MX321 Adjustments Over/V Sets the 125% over voltage trip point. This pot, like the Volts/Hz on the 300-2880 AVR is factory set and should not be adjusted in the field. Exc Trip Sets the 300% current level point. This pot, like the Volts/Hz on the 300-2880 AVR is factory set and should not be adjusted in the field. Dip Sets the rate of drop of output voltage after the generator set frequency falls below the UFRO point. Dwell Sets the maximum amount of time before the AVR forces the output voltage to start increasing back to normal after the generator set decreases below the UFRO point. RMS Sets the main operational characteristics of the MX-321. This pot, like the Volts/Hz on the 300-2880 AVR is factory set and should not be adjusted in the field. 8-6

Participant’s Guide

Integrated Generator Set Controls

Lesson: Automatic Voltage Regulator Adjustments

Stability Adjusts the amount of dampening in the AVR regulation circuit. The higher the dampening effect of this circuit, the slower the voltage changes. Volts Adjusts the AVR to a specific Reference Voltage with a particular load. This pot is adjusted after the Optimum Response Jumper is set for a specific alternator size. V/Trim Adjusts the amount of control an external option, connected at A1/A2, has on the AVR. Droop Adjusts the amount of cross-current compensation the AVR produces when a paralleling CT is connected to S1/S2. UFRO Adjusts the break point frequency for 100% 0.8 power factor load acceptance. This is the frequency at which the generator set output voltage starts to drop. Jumpers Frequency Selection No Link 1–2 1–3 2–3

sets AVR for use with 6-pole 50 Hz set (1000 RPM). sets AVR for use with 6-pole 60 Hz set (1200 RPM) sets AVR for use with 4-pole 50 Hz set (1500 RPM) sets AVR for use with 4-pole 60 Hz set (1800 RPM)

Frequency Selection Jumper comes set from 1–3 and must be reset for 60 Hz operation. Optimum Response A–B B–C A–C

sets AVR stability circuit for 550–1500 kW alternator. sets AVR stability circuit for 90–550 kW alternator. sets AVR stability circuit for 20–90 kW alternator.

Optimum Response Jumper comes set from A–B.

Participant’s Guide

8-7

Lesson: Automatic Voltage Regulator Adjustments

Integrated Generator Set Controls

VRAS-2 Shop Worksheet

300-2977

S1 S2 S3

Volts R-32

Do Not Adjust this potentiometer OH8Ć6

1

2

3

4

5

6

7

8

9 10

S&TT 10/00

Slide 8-6 AVR Inputs and Outputs — VRAS-2

Using the generator set and load bank in the shop, complete the worksheet for this regulator. S2 Position S1 1/2 Position S1 3/4 Position S3 1/2 Position S3 3/4 Position

No-Load Exciter

Voltage

Current

Full-Load Exciter

Voltage

Current

8-8

Participant’s Guide

Integrated Generator Set Controls

Lesson: Automatic Voltage Regulator Adjustments

SX-440 Shop Worksheet 60 C 50

A B C

STABILITY

UFRO LED Indicator

VOLTS

S2 S1 A2 A1

DROOP V/TRIM

ÉÉ ÉÉ ÉÉ

BLUE CAP.

Do Not Adjust potentiometers marked like this. OH8Ć7

S&TT 10/00

Slide 8-7 AVR Inputs and Outputs — SX-440

Using the generator set and load bank in the shop, complete the worksheet for this regulator. Frequency Selection Optimum Response Selection Volts Pot UFRO Pot

No-Load Exciter

Voltage

Current

Full-Load Exciter

Voltage

Current

Participant’s Guide

8-9

Lesson: Automatic Voltage Regulator Adjustments

Integrated Generator Set Controls

MX-321 Shop Worksheet K1 K2 P2 P3

P4 XX X 6

7 8 1 2 VOLTS

FREQUENCY SELECTION UFRO

I/LIMIT 321 RMS

DIP

DWELL STABILITY OPTIMUM RESPONSE SELECTION EXC U V W TRIP

OVER/V E0 E1 B0 B1

CBA

DROOP V/TRIM

S1 S2 S1 S2 S1 S2 A1 A2

Do Not Adjust potentiometers marked like this.

OH8Ć8

S&TT 10/00

Slide 8-8 AVR Inputs and Outputs — MX-321

Using the generator set and load bank in the shop, complete the worksheet for this regulator. Frequency Selection Optimum Response Selection Volts Pot UFRO Pot Stability Pot Dip Pot Dwell Pot

No-Load Exciter

Voltage

Current

Full-Load Exciter

Voltage

Current

8-10

Participant’s Guide

Integrated Generator Set Controls

Lesson: Alternator Output Reconnection

Alternator Output Reconnection This lesson presents an overview of reconnecting the output leads and the Current Transformers (CTs) on Onan and Newage alternators.

Objectives After completing this lesson, you should be able to: • State the basic connections used when reconnecting alternator output windings. • Identify Onan alternator winding markings. • Identify Newage alternator winding markings. • Identify the output voltage of an Onan or Newage alternator from the main stator connections. • Properly connect an Onan alternator simulator from a reconnection diagram. • Properly connect a Newage alternator simulator from a reconnection diagram.

Cummins is a registered trademark of Cummins, Inc. Onan is a registered trademark of Onan Corporation. Newage is a trademark of Stamford Corporation.

Participant’s Guide

9-1

Lesson: Alternator Output Reconnection

Integrated Generator Set Controls

Alternator Winding Connections

120 VAC 120 VAC

120 VAC

120 VAC Windings in Series provide 240 VAC from endĆtoĆend.

Windings in Parallel provide 120 VAC from endĆtoĆend.

OH9Ć1

S&TT 10/00

Slide 9-1 Alternator Winding Connections

Alternator windings can be connected in two basic configurations: Series

Parallel

All Onan and Newage reconnectible alternators have six windings, and non-reconnectible Onan and Newage alternators have either three or six windings depending on their design. The windings in the main stator can be either connected in Series or Parallel. If the windings are connected in Series, the output voltage from one end of a pair of windings will be twice the voltage of one winding. The current that these two windings can produce is limited by the current capacity of one winding. If the windings are connected in Parallel, the output voltage from one end of a pair of windings will be the same as the voltage of one winding. The current that these two windings can produce will be twice the current capacity of one winding. Series winding connections produce twice as much voltage output as one winding. The current output is the same as that carried by one winding. Parallel winding connections produce twice as much current output as one winding. The output voltage is the same as that produced by one winding. 9-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: Alternator Output Reconnection

Connecting Alternator Windings

Delta

Wye or Star

OH9Ć2

S&TT 10/00

Slide 9-2 Alternator Winding Connection Groups

Alternator windings that are connected in Series or Parallel can be further connected in two major connection groups; Delta, and Wye or Star Delta connections are used for several reasons: 1) Phase-to-phase current is 1.73 x the current in one phase. 2) The neutral leg does not have to be grounded. Wye or Star connections are used for several reasons: 1) Phase-to-phase voltage is 1.73 x the voltage from any phase to neutral. 2) Neutral lead is connected to Safety Ground at the service entrance of the building. Type Voltage ∅-N Wye/Star V of 1 winding Delta V of 1 winding

Voltage ∅-∅ 1.73 * V of 1 winding 2 * V of 1 winding

∅ Current I of 1 winding 1.73 * I of 1 winding

Delta connections are used for more current and to reduce ground fault damage. Some delta connected alternators do not require a neutral or ground connection. Wye connections are used for more voltage. Normally the neutral of a Wye alternator is connected to earth ground at the service entrance of the building. Participant’s Guide

9-3

Lesson: Alternator Output Reconnection

Integrated Generator Set Controls

Windings in Delta Connections L1

L2

L1

L0

L2

L0

L3 Windings connected in Series Delta

L3

Windings connected in Parallel Delta Often Phase B is connected to Neutral creating a Corner Grounded Delta"

OH9Ć3

S&TT 10/00

Slide 9-3 Windings in Delta Connections

Delta alternator connections do not always include a neutral connection. Series Delta connections • may have a Neutral connection for single-phase loads • may have just three output leads for three-phase loads. • with a neutral connection between L1 and L3 will have a voltage between L2 and Neutral equal to 1.73 times the L1 or L3 to Neutral voltage. Parallel Delta connections • do not normally have a neutral connection and therefore cannot power single-phase loads. • are sometimes used by power generation stations with Phase B (L2) connected to earth ground as a neutral connection. This may confuse technicians seeing this connection and reading Zero Volts from Phase B to Neutral or to the safety ground.

9-4

Participant’s Guide

Integrated Generator Set Controls

Lesson: Alternator Output Reconnection

Windings in Star Connections L2

L1

Windings connected in Parallel L2

L1 L0

L0

L3 Windings connected in Series OH9Ć4

L3

S&TT 10/00

Slide 9-4 Windings in Wye or Star Connections

Wye or Star alternator connections normally include a neutral connection. This connection will be at the point where the three phases come together. Series Wye or Star connections • normally have a Neutral connection for single-phase loads. Parallel Wye or Star connections. • also normally have a Neutral connection for single-phase loads • However, some Wye connections do not have a Neutral connection and therefore cannot power single-phase loads. All Wye or Star connected generator sets used with three-pole transfer switches must have their Neutral connection tied to ground at the service entrance of the building. All Wye or Star connected generator sets used as a separately-derived system with four-pole transfer switches must have their Neutral connection tied to ground at the generator set.

Participant’s Guide

9-5

Lesson: Alternator Output Reconnection

Integrated Generator Set Controls

Non-Reconnectable Windings L1

L2

L2

L3

OH9Ć5

L0

L1

L3

Windings in a nonĆreconnectible alternator connected in a WYE or Star

S&TT 10/00

Slide 9-5 Non-reconnectible alternator windings

The lowest cost alternators are non-reconnectible. These alternators can only produce one or two output voltages while producing the rated kilowatt output of the generator set. • The winding size limits the current through each winding to a low level. • In a normal genset, when the voltage changes, the current changes inversely to maintain a steady kilowatt output. • If the current cannot increase, when the voltage is decreased, the kilowatts produced by the generator set decreases.

9-6

Participant’s Guide

Integrated Generator Set Controls

Lesson: Alternator Output Reconnection

Onan Winding Markings L1 T1

L2 T4

Parallel Connection

L1 T1 T7

T4

T5

T10

T10

L2

T2

T12

T11

T9 T6

T6 T3

OH9Ć6

T8

T8

T11

T12

T9

T2

T5

T7

L3

T3

L3

Series Connection

S&TT 10/00

Slide 9-6 Alternator Reconnection – Onan markings

Reconnectible Onan alternators have twelve output leads numbered from T1 to T12. • T1, T4, T7 and T10 are always in the same output phase. • T2, T5, T8 and T11 are always in the same output phase. • T3, T6, T9 and T12 are always in the same output phase. The older Onan alternators produced an output voltage which electrically rotated counter-clockwise. • This is the reverse of the standard utility direction. • At that time, all US alternator manufacturers produced CCW rotating alternators. Since Onan purchased Newage Engineers in 1984, all Onan alternators have had a clockwise rotating electrical output.

Participant’s Guide

9-7

Lesson: Alternator Output Reconnection

Integrated Generator Set Controls

Onan Reconnection Diagram 8

CT21 7

T1

8 7 4 5 6

4

T10

T5 T11

5

8 7 Ċ 6 5

L2 (V)

T8

T4

Voltage Sensing Continuity Control Generator 347/600 Sensing Connect Input Sensing Lead TB21 Leads to -21 -23 -24 -25 -26

CT22

T2

T7

Sensing Lead

L1 (U)

L0 (N) T6

T12

T3

T9

CT23

L3 (W) 6

OH9Ć7

Onan Generator Schematic Diagram

S&TT 10/00

Slide 9-7 Sample Onan Reconnection Diagram

The sample Onan alternator reconnection diagram at the top of this page is just one of several ways to connect the output leads of an Onan alternator. This diagram shows a Parallel Wye, Parallel Star or Low Wye connection. Some things to note on this diagram are: • On which side of the CTs the dots are located. • Where the sensing leads connect to the alternator leads. • Where the individual lead numbers are shown and in which output phase each number is located. The diagram also shows a tabulation for TB21 connections. • The only windings that do not move are sensing leads 7 and 8. • Onan AVRs always get their reference voltage from these two sensing leads.

9-8

Participant’s Guide

Integrated Generator Set Controls

Lesson: Alternator Output Reconnection

Newer Newage Lead Markings L1

V1 L2

U1 U2

Parallel Connection

L1 U1 U5

V1 U2

V2

U6

V2

U5

L2

U6 W6

V5 V6

V5

V6

W5

W2

W2

W6

W1 W1

W5 OH9Ć8

L3

L3

Series Connection

S&TT 10/00

Slide 9-8 Alternator Reconnection – Newage markings

Reconnectible Newage alternators have twelve output leads numbered in three alpha-numeric sequences from 1 to 6. • U1, U2, U5 and U6 are always in the same output phase. • V1, V2, V5 and V6 are always in the same output phase. • W1, W2, W5 and W6 are always in the same output phase. Newage Engineers alternators have a clockwise rotating electrical output when used with normal rotation Cummins engines.

Participant’s Guide

9-9

Lesson: Alternator Output Reconnection

Integrated Generator Set Controls

Newage Reconnection Diagram 4 5 6 7 8

OH9Ć9

Newage Generator Wiring Diagram U2 V2 W2 W5 V5 U5

N W V

CT21

L1 (U) U6 V6 W6 W1

CT22

U1

V5

U5

V1

U U1 Voltage Sensing Continuity Control Generator 347/600 Sensing Connect Input Sensing Lead TB21 Leads to -21 8 8 -23 7 7 -24 4 Ċ -25 6 6 -26 5 5

L2 (V)

V1

V6 U2 U6

V2

W2

W6

W1

W5

L0 (N)

CT23

L3 (W) Newage Generator Schematic Diagram

S&TT 10/00

Slide 9-9 Sample Newage Reconnection Diagram

The sample Newage alternator reconnection diagram at the top of this page is just one of several ways to connect the output leads of a Newage alternator. The schematic and wiring diagrams show a Parallel Wye, Parallel Star or Low Wye connection. Some things to note on the wiring diagram are: • Where the sensing leads connect to the reconnection block. • Which reconnection studs are connected by jumper links. Some things to note on the schematic diagram are: • On which side of the CTs the dots are located. • Where the sensing leads connect to the alternator leads. • Where the individual lead numbers are shown and in which output phase each number is located. The diagram also shows a tabulation for TB21 connections. 9-10

Participant’s Guide

Integrated Generator Set Controls

Lesson: Alternator Output Reconnection

Alternator Reconnection – TB21 From Auxiliary terminal block or generator sensing leads

TB21 32

(AC Start Disconnect) To ECM

31

Resistor only used with Newage AVRs Sensing Lead 5

30 29 28 27

Sensing Lead 6 Sensing Lead 4 (Metering only) Sensing Lead 7

26 25

To AVR

24 23 22

To AVR To AVR

21 OH9Ć10

Sensing Lead 8

S&TT 10/00

Slide 9-10 Alternator Reconnection – TB21

TB21 is the main AC Control connection point inside the generator set control box. • TB21 always has terminals marked from 21 to 32. • Terminals 21 and 32 are the AC Starter Disconnect output (90–120 VAC) to the DC Control board (A11 ECM). • The alternator output terminals connect to TB21 through sensing leads four through eight. • This end of the sensing leads will not be moved, but when the generator set is reconnected, the other end may have to be moved.

Participant’s Guide

9-11

Lesson: Alternator Output Reconnection

Integrated Generator Set Controls

Onan Reconnection Simulator

L1 L2 L3 L4

Onan Simulator OH9Ć11

S&TT 10/00

Slide 9-11 Alternator Reconnection – Onan Simulator

Using a Service Manual for an Onan alternator and an Onan alternator simulator, construct the following connections: • Parallel Wye (Star) • Series Wye (Star) • Series Delta • Parallel Delta After you have completed each connection, show it to your instructor for grading. Make sure you show your instructor the manual and diagram you used to create the connection. Parallel Wye (Star)

Connected properly -

Proper Manual -

Proper Diagram -

Series Wye (Star)

Connected properly -

Proper Manual -

Proper Diagram -

Series Delta

Connected properly -

Proper Manual -

Proper Diagram -

Parallel Delta

Connected properly -

Proper Manual -

Proper Diagram -

9-12

Participant’s Guide

Integrated Generator Set Controls

Lesson: Alternator Output Reconnection

Newage Reconnection Simulator

L1

N

L2

W

L3

V

L4

U

Newage Simulator OH9Ć12

S&TT 10/00

Slide 9-12 Alternator Reconnection – Newage Simulators

Using a Service Manual for a Newage alternator and a Newage alternator simulator, construct the following connections: • Parallel Wye (Star) • Series Wye (Star) • Series Delta • Parallel Delta After you have completed each connection, show it to your instructor for grading. Make sure you show your instructor the manual and diagram you used to create the connection. Parallel Wye (Star)

Connected properly -

Proper Manual -

Proper Diagram -

Series Wye (Star)

Connected properly -

Proper Manual -

Proper Diagram -

Series Delta

Connected properly -

Proper Manual -

Proper Diagram -

Parallel Delta

Connected properly -

Proper Manual -

Proper Diagram -

Participant’s Guide

9-13

Lesson: Alternator Output Reconnection

Integrated Generator Set Controls

L1 (U)

L2 (V)

N W

L0 (N)

V U

L3 (W)

OH9Ć13

S&TT1/95

Slide 9-13 Alternator Reconnection – Newage Cutaway alternator

After looking at the cutaway Newage alternator in the shop, draw the output connection for this alternator in the above space. What is this alternator connection called?

What would you expect for an output voltage from a alternator connected in this fashion?

What voltage would be sensed at the Automatic Voltage Regulator?

9-14

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the AC Control

Troubleshooting the AC Control This lesson presents an overview of troubleshooting the Onan and Newage AC Controls.

Objectives After completing this lesson, you should be able to: • State the basic checks used with AC Controls. • Identify Onan AC Control test points. • Identify Newage AC Control test points. • State the most common AVR Input Voltages. • State the two most common causes of unstable output voltage. • Describe how to test for load-induced voltage instability. • Describe how to flash the field of a Cummins/Onan generator set.

Cummins is a registered trademark of Cummins, Inc.

Participant’s Guide

10-1

Lesson: Troubleshooting the AC Control

Integrated Generator Set Controls

AC Control Troubleshooting Diagram

Exciter Rotor

Rotating Diodes Main Rotor (–)

(+)

L1 Exciter Stator

Main Stator XX (–)

Excitation

L3

Reference Voltage

X (+)

L0

K1

CB21

K2

Drive Voltage

OH10Ć1

Slide 10-1 AC

L2 S&TT 10/00

Control Troubleshooting Diagram

Slide 10-1 is a block diagram showing the main parts of an AC Control System. The items in the dashed box (top) are rotating parts of the generator, and the items in the solid box (bottom) are stationary. The Field Circuit Breaker in this Figure is shown as it would be connected for a Newage SX-440, SX-460, or MX-321 AVR. CB21 would be connected differently for an Onan AVR. • Newage AVRs have the circuit breaker connected between terminals K1 and K2 on the AVR. In this connection, the actual DC exciter current flows through CB21. When the circuit breaker opens in an overcurrent condition, the excitation voltage drops to zero and the current through the exciter stator drops to zero. • Onan AVRs use a circuit breaker in the AC Regulator Drive voltage circuit. Onan AC Controls also use a Commutating Reactor (CMR21 or L21) which is not shown in Figure 1. CMR21 or L21 is in the regulator drive voltage circuit and helps to decrease noise to the AVR from non-linear loads..

10-2

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the AC Control

AVR Inputs & Output

AVR

Sensing Voltage (AC)

Excitation Voltage (DC)

Regulator Drive Voltage (AC) OH10Ć2

S&TT 10/00

Slide 10-2 Basic AVR Inputs and Output

Every AVR has two inputs and one output.

INPUTS • Sensing Voltage Sample of the generator output voltage. This is usually 208 to 240 VAC

• Regulator Drive Voltage Input to the AVR that is rectified to produce the excitation voltage. This voltage can come from the generator output, or from a Permanent Magnet Generator (PMG). This is usually 140 to 260 VAC.

OUTPUTS • Excitation Voltage DC pulses to the exciter stator which, produces the generator output voltage when amplified through the generator. This is usually 2 to 20 VDC

Participant’s Guide

10-3

Lesson: Troubleshooting the AC Control

Integrated Generator Set Controls

AC Control System Flow Diagram

Rotating Diodes

Exciter Rotor

Main Rotor (–)

Exciter Stator

(+)

Main Stator XX (–)

Excitation

L1 L3

Reference Voltage

X (+)

L0

K1

CB21

K2

Drive Voltage

L2

OH10Ć3

S&TT 10/00

Slide 10-3 AC Control System Flow Diagram

Each part in the AC Control System has an input (or inputs) and an output; refer to the above diagram to see the “flow” through the generator system. Part Name

Input

Output

AVR

Sensing Voltage

Excitation Voltage

Regulator Drive Voltage

10-4

Exciter Stator

Excitation Voltage

Magnetic Flux

Exciter Rotor

Magnetic Flux

3-Phase AC Voltage

Rotating Diodes

3-Phase AC Voltage

DC Voltage

Main Rotor

DC Voltage

Magnetic Flux

Main Stator

Magnetic Flux

1-Phase AC or 3-Phase AC Voltage

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the AC Control

QUICK CHECKS FOR AC CONTROLS This set of quick checks assumes that the generator does not have proper output voltage. There are some basic checks that can be done to check the AC control system. First, stop the generator set and disconnect the exciter stator leads from the exciter stator and insulate them so they cannot short or be grounded. Second, start the generator set and check for output voltage at the main stator terminals. 1.

Is there residual voltage at the output of the Main Stator windings when the exciter leads are disconnected? (LV 5–20 VAC, MV 5% of Output)

• YES: The main stator windings are good. • NO: The main stator windings are not good. Check resistance as shown in the Service Manual. 2.

If the residual voltage is good, stop the set and reconnect the exciter leads to the exciter stator. Start the set. Has the output voltage increased?

• YES: Adjust the Coarse Voltage Adjust pot on the AVR. • NO: Check to see that CB21 is closed. If CB21 is OK, flash the field using the procedure in the Service Manual. 3.

When you flash the field, does the output voltage from the Main Stator increase?

• YES: The Exciter Stator, Rotating Diodes and Main Rotor are OK. • NO: There is a problem with the Exciter Stator, Exciter Rotor, Rotating Diodes, or Main Rotor. Perform checks as shown in the Service Manual. 4.

If the output voltage increased when you flashed the field, does the output stay up when the flash is removed?

• YES: The Exciter Stator, Rotating Diodes, Main Rotor and AVR are OK. • NO: There is a problem with the Automatic Voltage Regulator. Perform checks as shown in the Service Manual. 5.

Put a full load on the generator set. Does the generator set output stay up after the generator set has responded to the load?

• YES: The generator set is OK. • NO: Check Rotating Diodes. Replace them if any diode is open or shorted. Participant’s Guide

10-5

Lesson: Troubleshooting the AC Control

Integrated Generator Set Controls

Flashing The Field

Exciter Stator

NOTE: Connect battery + terminal to AVR + exciter terminal. Connect battery – terminal through a resistor or lamp and a diode to prevent battery damage.

CB21

L1 Main Stator (–)

AVR (+)

(–)

(+)

L3

Reference Voltage

L0

L2

300 Volt, 5 Amp diode OH10Ć4

S&TT 10/00

Slide 10-4 Flashing the Field

If the generator is disassembled or dropped, the residual magnetism in the main rotor can be reduced enough so the regulator cannot get itself started with the residual voltage out of the main stator windings. Onan recommends that you use the resistors listed in the following chart, or a light bulb, as a current limiting device when flashing the field of a generator set. • 6 Volts = 10 Ohms • 12 Volts = 20 Ohms • 24 Volts = 40 Ohms DO NOT Flash the field for more than five (5) seconds, or you may damage the regulator or the exciter stator windings. Make sure you have a diode in the field flash apparatus you use to prevent the regulator from overcharging the battery. Batteries can explode when overcharged. The field flash apparatus (shown in heavy lines should be touched to either the exciter terminals at the regulator, or at the exciter stator. Make sure you observe proper polarity when connecting the field flash circuit. Remember, the exciter field circuit is not referenced to ground, so you have to touch both of the exciter terminals to create a current flow in the exciter stator winding. 10-6

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the AC Control

Two Most Common Failures Rotating Diodes - #2

Exciter Rotor

Main Rotor

R21 - #1 Exciter Stator

(–)

(+)

Main Stator XX (–)

Excitation

L1 L3

Sensing Voltage

X (+)

L0

K1

CB21

K2

Drive Voltage

OH10Ć5

L2 S&TT 10/00

Slide 10-5 The two most common causes of unstable output voltage

Most AC controls and generators work properly. However, sometimes you will come upon a generator set which will not produce voltage, or the voltage is unstable, or the voltage is slightly high or low. • The most common genset failure which causes unstable output voltage is the R21 variable resistor. This resistor vibrates when the generator set operates. This can cause corrosion between the resistor terminals and the wires connecting to these terminals. The connections then “make and break” as the control panel moves. This causes the voltage adjust circuit to change resistance and the output voltage changes also. • The second most common cause of unstable output voltage is a failure or loose connection in the rotating diodes. When these connections “make and break” the current going to the main rotor changes and the output voltage also changes. To determine if the cause of the problem is in the genset or the load, disconnect the load from the generator set and run the set. If the output voltage is steady, the problem is most likely a load-induced problem. If the output voltage is unstable, the problem is in the generator set. Load-Induced Problems: Harmonic generation, unbalanced loads, non-linear loads are the three most common load-induced problems. Participant’s Guide

10-7

Lesson: Troubleshooting the AC Control

Integrated Generator Set Controls

Questions to ask yourself and others 1.

Has anyone worked on the set recently? What did they do? Maybe the last work was done improperly, or the part that was installed has failed.

2.

What was happening just before the problem started? Was the load changed recently? Did the sound of the generator change in any way? Were there any different sounds or smells from the generator recently?

3.

Are all components connected properly? One of the best things that a technician can do to solve a problem is to perform a good visual inspection. Many times you will find possible future problems that you can prevent from becoming failures when they are repaired early.

Common Failures 1.

Because of vibration and ageing, a bad remote voltage adjust potentiometer (R21) is the most common cause of unstable output voltage.

2.

The second most common cause of unstable output voltage is bad rotating diodes.

3.

The third most common cause of unstable output voltage is a non-linear load on the generator set which overpowers the AVR and the load ends up controlling the voltage.

10-8

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the AC Control

Troubleshooting AC Controls

Magnetic Coupling

AVR CB21 OH10Ć6

Magnetic Coupling L1 L3

L0

L2 S&TT 10/00

Slide 10-6 AC Control Troubleshooting Diagram

When troubleshooting a problem in an AC Control System, you have to remember that some things are easier to check than others. For instance, you cannot check anything on the rotating portion of the generator without doing some sort of disassembly of the generator set. To become an expert troubleshooter, it helps to think of the generator set and its three major parts (engine, AC control, DC control) as systems of related components. When looking for a possible failed part in the AC Control system, it helps to know what the proper indication would be at the point you are going to check. The easiest place to check Reference Voltage is usually at TB21 inside the control box. The Reference Voltage into the AVR is always on terminals 22 and 23. The MX-321 has three voltages on TB21 terminals 22, 23, and 25 since it measures all three phases of the output voltage. The easiest place to check Excitation Voltage is usually at the Exciter Stator terminals F1 / F2 or X / XX.

Participant’s Guide

10-9

Lesson: Troubleshooting the AC Control

Integrated Generator Set Controls

Easy-Likely Troubleshooting Checks There are four common problems that are seen in AC Controls: • No output voltage • Low output voltage • High output voltage • Unstable output voltage

No Output Voltage If there is Reference Voltage into the AVR and no Excitation Voltage out of the AVR, there are several things that can be checked. • If the AVR is an Onan VRAS-2, is there a jumper between terminals 3 & 4 of the AVR? If there is no jumper on the AVR, there will not be any Regulator Drive input to rectify into Excitation. • If the AVR is a Newage AVR, check to see that terminals K1 and K2 are connected with a jumper or the CB21 circuit breaker. • Check to see that the Field Circuit Breaker (CB21) is connected and makes a complete circuit to the AVR.

Low Output Voltage • Check Coarse Volts pot on the AVR. • Check connection of T21 for older Onan generator sets. • Check ampere load of generator set to see if the generator set is overloaded. • Check to see if “UFRO” LED is lit on Newage AVRs. • Check connection of generator output leads. • Check rotating diodes.

10-10

Participant’s Guide

Integrated Generator Set Controls

Lesson: Troubleshooting the AC Control

Easy-Likely Troubleshooting Checks High Output Voltage • Check Over Voltage pot setting and connections. • Check Coarse Volts pot on the AVR. • See if the “I/Limit” or “EXC Trip” pots have been changed on the AVR.

Unstable Output Voltage • Check R21 condition and connections. • Check kW meter against calculated KVA to see if load power factor is out of allowable range and overloading the generator set. • Check “Stability” pot and adjust if needed. • Check frequency at which the “UFRO” LED lights, and adjust if needed.

Participant’s Guide

10-11

Lesson: Troubleshooting the AC Control

Integrated Generator Set Controls

This page intentionally left blank

10-12

Participant’s Guide

Cummins is a registered trademark of Cummins Engine Company PowerCommand is a Registered Trademark of Onan Corporation Powerful Solutions is a trademark of Onan Corporation