Docslide.us Cummins Efc Troubleshooting Guide

CUMMINS INDIA LIMITED

ELECTRIC FUEL CONTROL GOVERNOR

CUMMINS DIESEL SALES & SERVICE (I) LTD 35A/ 1 / 2 , Erandwana, Pune 411 038.

FOREWORD The electric fuel control ( EFC) governor is used on the PT fuel system. The EFC governor can be adjusted for isochronous or droop applications. This TROUBLE SHOOTING GUIDE contains a list of trouble symptoms & their solutions for solving problems on both indigenous & imported EFC governors fitted on Generator drive applications.

Cautions & Warnings! 1. Do not connect governor Power supply terminals directly to the battery charger. Connect the Power supply terminals with the correct polarity to the battery directly, without looping with the other equipments. Do not disconnect battery while engine is in running condition. For checking continuity & resistances of any EFC Components , Please disconnect the battery supply. 2. Do not apply external supply / 24 V directly across the controller terminals 6 , 7,(for indigenous) & 3 & 4 (for imported) ---- Actuator connections. For giving 24 V to actuator for testing purpose, remove the connections of the actuator terminals & then give supply to the actuator . 3. Use proper screwdriver for adjustment of potentiometers. 4.

Check the ripple voltage on D.C. supply using AC range on a DIGITAL MULTIMETER, on Power supply terminals of the controller. It should be less than 1.5 Vac

5.

Handle the actuator with great care, never hold it by its sleeve. Always hold it by its base only.

6.

When battery supply to the Solid State Potentiometer ( SSP) is disconnected , it has be set again when reconnected. Do not disconnect the power supply to the SSP .

7. While reporting a problem or for a warranty claim duly filled check list of the related symptom & the basic checks must accompany the service report.

1

PREFACE

Majority of the problems are generated because of ... • • • • •

Dirt & air entry in the fuel system Improper DC voltage supply. RPM signal distortion due to improper shielding. Improper adjustment on the EFC controller. Improper wiring.

The following Basic checks will take care of the above mentioned causes. These checks are mandatory for all problems related to EFC Tools required: Digital multimeter(Do not use analog meter) EFC Manual. Small screwdriver.( Taparia Make - No.911) Allen key size - 3/ 32"

Remember! Once set properly, EFC controller does not need frequent adjustments ! ! ! Please float all your querries / suggestions / additions / deletions / improvements / feedbacks, to the Electronics Cell at CDS&S (I) Ltd. PUNE

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Basic Checks. Wiring Checks. ( Cold Checks ) 1 : Check wiring as per the wiring diagram of the engine model . Please refer the respective product user manual for correct wiring part number. For Indeginious EFC Controller : Bulletin No. 3243692-00 For Imported EFC Controller : Bulletin No. 3379231-03 2 : Check end to end continuity of the harness at the same time see that the particular wire is not shorted with any other wire and is not showing continuity with it. This test is to conform electrical connections. Also check end to end continuity of the shield ( wire) & make sure that only one end of the shield is connected to negative of the battery, the other end remains open.

1 : Mag Pick up Part

Desired reading

Actual reading

a : Resistance of Mag. Pick Up with & with out connector.

80 - 1600 Ohms

-------Ohms Replace in case of Deviation

b : Check for body short*

> 100K Ohms

--------Ohms Replace in case of Deviation

c : Gap between the tip of the pick up and ring gear tooth tip.

0.028” to 0.042”

--------More /less

3

Action

Correct

2 : Actuator Part

Desired reading

Actual reading

Action

a : Actuator Resistance

7 to 9 Ohms

-------Ohms

Replace in case of Deviation

b : Check for body short*

>100K Ohms

-------Ohms

Replace in case of Deviation

3 : Remote Potentiometer( For KCL controller) Part

Desired reading

Actual reading

a : Total Resistance

10 K Ohms

-------Ohms

Replace in case of Deviation

-------Ohms

Replace in case of Deviation

b : With respect to variable terminal 0 - 10K Ohms

Action

4: Remote Potentiometer (For Imported Controller) Part

Desired reading

a : Total Resistance

Actual reading

(120 + 5) K Ohms

b : With respect to variable terminal 0 to (120 + 5)K Ohms

Action

------Ohms Replace in case of Deviation ------Ohms Replace incase of Deviation

SOLID STATE POTENTIOMETER : FOR INDIGENOUS CONTROLLER ( 3873853 ) USE SSP WITH P.No. 3877372. FOR IMPORTED CONTROLLER (3062322 ) USE SSP WITH 4

P.No 3392055.

SERVICE PARTS TOPICS : FOR INDIGENOUS SYSTEM USE SPT No. 3242526. :FOR IMPROTED SYSTEM USE SUPPLEMENTNo.3379231. CABLES TO BE USED WITH SSP'S : a. For connecting out put & ground terminals ( of SSP ) to controller terminals 1 & 2 ( for indigenous controller) / 8 & 11 of imported controller --use 2 core 1.5 sq. m.m shielded cable. b. For connecting -- Raise input & lower input on to the panel --- use 1 Sq. m.m wire. a. Power supply connection : Use 1.5 Sq. m.m wire. Check the above wiring & replace in case of any deviation. For detailed connection -- Refer respective diagrams enclosed herewith. For checking the Solid State Potentiometers : 1. Give 24 Vdc supply to the Power supply terminals of the SSP. 2. Connect the multimeter ( d.c.range --40V ) to terminals output & common of the SSP. 3. Press the raise button on the SSP & observe the voltage rise on your multimeter, simultaneously see that the Raise LED on the SSP is Glowing. Also observe the Limit red LED glowing when the Out put reaches the limit. ---4. For SSP with P.No. 3877372 --- O/p varies from 0Vdc to 2Vdc. For SSP with P.No. 3392055 --- O/p varies from 4Vdc to 6Vdc. 5. Similarly press the lower button & check if the voltage goes down & the limit LED glows when the voltage reaches the lower limit. IF ANY LED'S OF THE SSP IS NOT GLOWING WHEN THE PARTICULAR FUNCTION IS ON THEN REPLACE THE SSP. For Ex : When the Raise button is pressed -- the raise LED should glow. : When the raise limit is reached --the raise LED with the Limit LED should Glow.

CAUTION : IF THE POWER SUPPLY TO THE SSP IS DISCONNECTED, THE SSP HAS TO BE SET AGAIN IF RECONNECTED. THEREBY POWER SUPPLY TO THE SSP SHOULD NOT BE DISCONNECTED AT ANY TIME. In cases of problems like hunting or engine overspeeding etc , please disconnect the Potentiometer & carry out the trouble shooting. Potentiometer can also be the cause of the problem.

5 : Run / Idle Switch

( Continuity between two terminals )

5

Part

Desired reading

Actual reading

a : In RUN mode ( open) incase of

>100K Ohms

------Ohms

Replace