Areva m231 Manual

MiCOM M231

Service Manual MiCOM M231

M231/EN M/B11 Page 1/32

CONTENT 1.

INTRODUCTION

3

2.

SYSTEM MODES

4

2.1

Connection mode

4

2.1.1

Valid measurements

4

2.2

Power mode

5

2.3

Operating energy quadrants

6

3.

INSTRUMENTATION

7

3.1

Measurements

7

3.1.1

Voltage

7

3.1.2

Current

7

3.1.3

Angles between Phases

7

3.1.4

Frequency

7

3.1.5

Harmonics

7

3.2

Power, power factor and energy

8

3.2.1

Power

8

3.2.2

Power factor

8

3.2.3

Energy

8

3.3

Demand values

9

3.3.1

Real time clock

9

3.3.2

Maximum demands (MDs)

9

3.3.3

Average demands

9

3.3.3.1

Fixed window

9

3.3.3.2

Sliding window

9

3.3.3.3

Thermal Demand

9

3.4

Digital Outputs

9

4.

COMMUNICATIONS

10

4.1

RS232 communications

10

4.2

RS485 communications

10

5.

USER INTERFACE MENU STRUCTURE

11

5.1

Measurements menu

12

5.1.1

Energy meters menu

13

5.2

Settings

14

5.2.1

Password menu

15

5.2.2

Language menu

16

5.2.3

Display menu

17

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Service Manual MiCOM M231

5.2.4

Real time clock menu

17

5.2.5

Pulsed outputs menu

18

5.2.6

Reset MD Menu

18

5.2.6.1

Synchronisation

18

5.2.6.2

Reset MD since last reset

18

5.2.6.3

Reset MD for Present Period

19

5.2.7

Maximum demand calculations menu

20

5.2.8

Communication Menu

21

5.2.9

Connection menu

21

5.2.9.1

CT Ratio

22

5.2.9.2

Connection input

22

5.2.9.3

VT Ratio

22

5.3

Battery

23

5.3.1

Battery replacement

23

5.4

Default settings

23

6.

TECHNICAL DATA

24

6.1

Ratings

24

6.1.1

Voltage input

24

6.1.2

Current input

24

6.1.3

Frequency

24

6.1.4

AC auxiliary supply

24

6.1.5

DC auxiliary supply

24

6.2

Accuracy

25

6.3

Relay outputs

25

6.4

Real time clock

25

6.5

Back up battery

25

6.6

Communication ports

26

6.6.1

RS232 Port

26

6.6.2

RS485 Port

26

6.7

Product Safety

26

6.8

Environmental withstand

27

6.8.1

Atmospheric environment

27

6.8.2

Construction

27

6.9

CT and VT connections

27

6.10

Power supply, communications and pulsed output connections

30

6.11

Dimensions

31

Service Manual

M231/EN M/B11

MiCOM M231

1.

Page 3/32

INTRODUCTION The M231 Measurement Centre integrates a number of measurement, monitoring and metering functions in the same unit for comprehensive power system management. The use of numerical technology achieves high accuracy over a wide dynamic measuring range for instantaneous and integrated power system parameters. The M231 also provides a host of other measurement, monitoring and metering facilities as detailed below:

•

•

•

Instrumentation.

−

Measured parameters as shown in Table 1.

−

High accuracy, typically 0.5% for current and voltage.

−

True RMS measurement.

−

Display of primary quantities.

Metering Facilities.

−

Active and reactive energy metering.

−

Demand metering.

User friendly design.

−

Large clear liquid crystal display.

−

Programming from front panel and communications port.

−

RS485 or RS232 Modbus protocol is available.

The device is therefore ideally suited to applications where continuous monitoring of a single or three-phase system is required. Instantaneous Measurements

Parameters

Phase voltages

Ua, Ub, Uc

Average phase voltage

U

Line voltages

Uab, Ubc, Uca

Average line voltage

U∆

Current

Ia, Ib, Ic, It

Neutral current

In

Active power

Pa, Pb, Pc, Pt

Reactive power

Qa, Qb, Qc, Qt

Apparent power

Sa, Sb, Sc, St

Power factor

cosϕa, cosϕb, cosϕc, cosϕt

Frequency

Frequency

Total Harmonic Distortion

%THD Ia, %THD Ib, %THD Ic

Total Harmonic Distortion

%THD Ua, %THD Ub, %THD Uc

Total Harmonic Distortion

%THD Uab, %THD Ubc, %THD Uca

Integrated/ Maximum Demands Maximum demand

It, Pt, Qt, St

Energy

Wht, varht

TABLE 1 : MEASURED PARAMETERS

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MiCOM M231

2.

SYSTEM MODES

2.1

Connection mode The connection mode of the M231 is menu-configurable. The following options are available:

2.1.1

•

1b - single phase connection,

•

3b - three-phase, three-wire connection with balanced load,

•

4b - three-phase, four-wire connection with balanced load,

•

3u - three-phase, three-wire connection with unbalanced load

•

4u - three-phase, four-wire connection with unbalanced load.

Valid measurements Table 2 lists the valid measurements for each connection type. Parameter

Connection type 1b

4b

4u

•

•

Ub

•

•

Uc

•

•

•

•

•

•

•

•

•

•

•

•

•

Uca

•

•

•

•

U∆

•

•

•

•

•

•

•

•

Ib

•

•

•

•

Ic

•

•

•

•

•

•

•

•

Ua

U

•

•

Uab Ubc

Ia

It

3b

•

•

•

•

In cosϕa

•

•

cosϕb

•

•

cosϕc

•

•

•

•

•

•

•

Pb

•

•

Pc

•

•

•

•

•

•

Qb

•

•

Qc

•

•

•

•

cosϕt

•

Pa

•

Pt

•

Qa

•

Qt

3u

•

•

•

•

•

•

•

Service Manual

M231/EN M/B11

MiCOM M231

Page 5/32

Parameter

Connection type

•

•

•

Sb

•

•

Sc

•

•

Sa

•

St

•

•

•

•

•

%THD Ia

•

•

•

•

•

%THD Ib

•

•

•

•

%THD Ic

•

•

•

•

•

•

%THD Ub

•

•

%THD Uc

•

•

%THD Ua

•

%THD Uab

•

•

•

•

%THD Ubc

•

•

•

•

%THD Uca

•

•

•

•

TABLE 2 : VALID MEASUREMENTS FOR EACH CONNECTION TYPE. 2.2

Power mode The power mode is used for the signing of power measurements. The user cannot set the M231 power mode. It is defined as follows:

•

When displaying active power, a positive sign indicates export power (a consumer) whilst a negative sign indicates import power (a generator).

•

When displaying reactive power, a coil symbol indicates an inductive load (a consumer) whilst a capacitor symbol indicates a capacitive load (a generator).

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2.3

MiCOM M231

Operating energy quadrants The operating energy quadrants are used to determine which types of energy are added to the energy counters. The user may modify the operating energy quadrants via the remote communications interface. The default operating energy quadrants are as follows:

•

Counter 1 – displays active energy: only export energy (a consumer) is measured.

•

Counter 2 - displays reactive energy: only import reactive energy (a consumer) is measured.

The four power quadrants are defined in Figure 1. The user may customise the energy meters to accumulate the desired values of energy to application specific requirements. Using the Modbus data register the user must enter the following information for each counter:

•

Energy type - active or reactive.

•

Operating energy quadrants - select the required operating energy quadrants.

•

Absolute Value - if this is chosen only the absolute value of energy recorded.

•

Inverted value - if this is selected the polarity of the power used to accumulate the desired energy is reversed.

Q (Cap) Lagging vars to generator

Import Q Import P

Qua rant 2

S

Qua rant 1

Import Q Export P

S

Q

Q

P

P

Power to generator

Power to consumer

P --

P +

P Q

Q

S

Export Q Import P

Qua rant 3

S Qua rant 4

Lagging vars to consumer Q (Ind) FIGURE 1 : POWER QUADRANTS

Export Q Export P

Service Manual MiCOM M231

3.

INSTRUMENTATION

3.1

Measurements

M231/EN M/B11 Page 7/32

With the increase in harmonics present in today's power systems, due to the increased use of electronic loads such as computers, variable frequency drives, etc. it is important, when accurate monitoring of electrical parameters is required, to use a measuring technique that allows for their presence. Conventional measurement methods, that use a mean sensing technique, respond to the mean or average of the input waveform. This is only accurate when the input waveform approaches a pure sinusoid. The M231 uses a true RMS (root-mean-square) measurement technique that provides accurate measurement with harmonics present up to the 15th harmonic. The M231 reads 64 samples per cycle and the true RMS measurement is obtained using these sampled values. 3.1.1

Voltage All versions of the M231 except for the 3-phase 3-wire versions, measure the true RMS value of the phase voltages (U a, Ub, Uc) connected to the unit. The three line voltages (U ab, Ubc, Uca), average phase voltage (U) and average line voltage (U ∆) are calculated from these measured parameters. For 3-phase 3-wire balanced systems, the M231 creates a virtual neutral internally. The 3-phase 3-wire versions of the M231 measure the true RMS value of the phase to phase voltage. The available phase, line and average voltages can be viewed on the M231 display or via the remote communications link.

3.1.2

Current The M231 measures the true RMS value of the phase currents ( Ia, Ib, Ic) connected to the unit. The neutral current ( In), the average of all phase currents and the sum of all phase currents (It) are calculated from the three phase currents. The available phase currents, average current and neutral current can be viewed on the M231 display or via the remote communications link whilst the sum of all phase currents is only available via the remote communications link.

3.1.3

Angles between Phases Angles between phases indicate the angles between the vectors of phase voltages. A positive mark indicates correct phase sequence, while a negative mark indicates an opposite phase sequence of the measured system.

3.1.4

Frequency The system frequency is calculated from the time period of the measured voltage and can be viewed from both the M231 display and the remote communications link.

3.1.5

Harmonics The percentage total harmonic distortion (%THD) value is the ratio of the sum of the powers of the harmonic frequencies above the fundamental frequency to the power of the fundamental frequency. This sum of the powers is a geometric total, formed by taking the square root of the sum of the squares of the amplitude of each of the harmonics. The M231 provides %THD values for each phase current, each phase voltage, and for the line voltages. This feature is an order option.

M231/EN M/B11 Page 8/32

3.2

Power, power factor and energy

3.2.1

Power

Service Manual MiCOM M231

The M231 provides accurate measurement of active (Pa, Pb, Pc, Pt), reactive (Qa, Qb, Qc, Qt) and apparent power (S a, Sb, Sc, St). For a four-wire system the powers are calculated both for each phase separately and as a total. For a three-wire system only total power values are measured. When displaying active power, a positive sign indicates export power (a consumer) whilst a negative sign indicates import power (a generator). When displaying reactive power, a coil symbol indicates an inductive load (a consumer) whilst a capacitor symbol indicates a capacitive load (a generator). All the available power parameters can be viewed using either the M231 display or via the remote communications link. 3.2.2

Power factor The power factor is calculated as a quotient of active and apparent power for each phase separately (cosϕa, cosϕb, cosϕc) and as a total (cos ϕt). A positive sign and a coil symbol denotes an inductive load (a consumer) whilst a negative sign and a capacitor symbol defines a capacitive load (a generator). All available power factor parameters can be read from the M231 display or via the remote communications link.

3.2.3

Energy Four counters are available so that energy in each of the four quadrants can be measured. The configuration of the four counters can be adapted to the customer's needs via the remote serial communications link. All four energy measurements may be viewed using either the M231 display or a remote communications link.

Service Manual MiCOM M231

3.3

M231/EN M/B11 Page 9/32

Demand values The M231 provides maximum demand values from a variety of average demand values (fixed window, sliding window and thermal) for the following electrical parameters:

3.3.1

•

Total active power (Pt).

•

Total reactive power (Qt).

•

Total apparent power (S t).

•

Sum of phase currents (It).

Real time clock The M231 is provided with a built-in real time clock. It is intended for registration of time of the occurrence of Maximum demands, and for synchronisation of the time interval.

3.3.2

Maximum demands (MDs) The M231 stores the maximum demand value since last reset and its corresponding time stamp. The unit also displays the present or 'dynamic' maximum demand.

3.3.3

Average demands

3.3.3.1

Fixed window The fixed interval method calculates an average demand value over a fixed time period. The period can be set over the range 1 to 255 minutes.

3.3.3.2

Sliding window The sliding window technique allows the user to divide the time period into a number of subperiods. The average demand value over the demand period is displayed, however, after the initial demand period has elapsed, the demand value will be updated by the addition of a further sub-period, thus creating a 'sliding window' measurement. For example if the total period is 30 minutes (consisting of 5 sub-periods of 6 minutes duration), after the first 5 subperiods have elapsed a new window will be added and the oldest window will be deleted, thus creating a sliding window. The number of sub-periods may be set between 2 to 15.

3.3.3.3

Thermal Demand The thermal demand option will provide an exponential thermal characteristic, based on the bimetal element principal. Maximum demand and the time of its occurrence are stored in the unit.

3.4

Digital Outputs The M231 can be supplied with two pulsed outputs that can be used for external monitoring of energy consumption. The energy measuring via the pulsed outputs corresponds to the basic energy measurement on the M231 display. The pulsed outputs' energy measurement can be adapted to the customers needs via the remote communications link.

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4.

MiCOM M231

COMMUNICATIONS The M231 is supplied with either RS232 or RS485 electrically isolated communications and should be specified at ordering. The communications protocol is MODBUS RTU, which is detailed in the Appendix of this Service Manual. The communications service enables remote viewing of measurements and viewing and setting of system parameters.

4.1

RS232 communications The connection of RS232 communications between the M231 and a PC is detailed in Table 3. The maximum connection length is 15 metres. M231 terminal

9 pin D connector (PC)

25 pin D connector (PC)

Rx (19)

Tx (3)

Tx(2)

GND (20)

GND (5)

GND(7)

Tx (21)

Rx (2)

Rx(3)

TABLE 3 : RS232 CONNECTIONS 4.2

RS485 communications RS485 communications enables simultaneous connection to a maximum of 32 communicating devices. Two-wire RS485 only is used. For RS485 communications, the PC will require either an internal RS485 communications port or an external RS232/RS485 interface. In both cases the device must provide automatic RS485 data flow control. The maximum connection length is 1000 metres. Conductors Data+ and Data- should be terminated with a 120Ω terminating resistor on the last unit in the RS485 link. Table 4 details the RS485 connections. M231 terminal

RS485

19

DATA +

20

shield

21

DATA -

TABLE 4 : RS485 CONNECTIONS

Service Manual

M231/EN M/B11

MiCOM M231

5.

Page 11/32

USER INTERFACE MENU STRUCTURE The settings, measurements and functions of the M231 can be accessed from either the front panel or the remote communications link. The menu structure of the M231 is navigated using the four keys on the front panel. Throughout this section the arrows in the diagrams relate to pressing the corresponding key on the front panel. The M231 has four levels of access:

•

L0 - No password is required. This allows the user to browse through the measurements and the set display.

•

L1 - Level 1 password required. In addition to the access rights of L0, the following are available; set the real time clock, reset and synchronise maximum demand and reset the energy meters.

•

L2 - Level 2 password required. In addition to the rights of L0 and L1 the following are available; setting of pulsed outputs, demand calculations, communications settings and connection modes.

•

L3 - Level 3 password required. This level is accessible only via the remote communications interface and is used for factory calibration and service.

The M231 is supplied with both L1 and L2 passwords set to AAAA. AAAA passwords offer no level of protection; all measurements and settings can be modified. The L1 and L2 passwords must be changed from AAAA to activate password level protection. When the M231 is first connected to the power system the user is greeted with the message shown in Figure 2. Measurement Centre M231

FIGURE 2 : GREETING After a period of five seconds the M231 display automatically defaults to display the energy meters as shown in Figure 3.

1

EXPORT

kWh

0000000.00 2

IMPORT

kvarh

0000000.00 FIGURE 3 : ENERGY METERS

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5.1

MiCOM M231

Measurements menu Figure 4 illustrates the measurements menu structure. The user can browse through the available measurements without entering any password. The user will automatically be prompted to enter a password where required to modify settings or reset measurements.

10

EXPORT

kWh

30

IMPORT

kWh

0000000.00

0000000.00

20

40

IMPORT

kvarh

0000000.00

EXPORT

kvarh

0000000.00

1 2 3 4

* * * *

RESET RESET RESET RESET

SETTING

09:APR:2004 07:12:34

PF TOTAL

+0.003 ß PHASE a +0.003 ß PHASE b +0.003ß PHASE c

+0.003ß FREQUENCY

00.00Hz

000.00 W+ 000.00 VAR 000.00 VA

TOTAL TOTAL TOTAL

000.00 W+ PHASE a 000.00 W+ P HASE b 000.00 W+ P HASE c

000.00 VAR PHASE a 000.00 VAR P HASE b 000.00 VAR PHASE c

000.0 V 000.0 V 000.0 V

LINE a -b LINE b -c LINE c - a

AVERAGE 000.00 V

000.56% THD U LINE a -b 000.56% THD U LINE b-c 000.56% THD U LINE c-a

000.0 V 000.0 V 000.0 V

PHASE a PHASE b PHASE c

AVERAGE 000.00 V

000.5 6% THD U PHASE a 000.56% THD U PHASE b 000.56% THD U PHASE c

0000.0 mA PHASE a 0000.0 mA PHASE b 0000.0 mA PHASE c

NEUTRAL 0.000 A AVERAGE 0000.0 mA

PRESENT MD Pt= +00.00 W MD at 05.APR 08:12 Pt= +000.0 W

PRESENT MD It= +00.00 mA MD at 05.APR 08:12 It= +000.0 mA

000.00 VA P HASE a 000.00 VA P HASE b 000.00 VA P HASE c

-041.56˚ a-b +046.31˚ b-c -001.56˚ c-a

000.56% THD I PHASE a 000.56% THD I PHASE b 000.56% THD I PHASE c

PRESENT MD Qt= +00.00 var MD at 05.APR 08:12 Qt= +000.0 var

FIGURE 4 : MEASUREMENTS MENU

PRESENT MD St= +00.00 VA MD at 05.APR 08:12 St= +000.0 VA

Service Manual

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MiCOM M231

5.1.1

Page 13/32

Energy meters menu A level 1 or 2 password must be entered to gain access to reset the energy meters shown in Figure 5. The user can either reset any of the four energy counters separately, or reset energy counters 1 to 4 simultaneously. To reset the chosen counter the → key must be held for five seconds.

30 IMPORT kWh 0000000.00 40 EXPORT kvarh 0000000.00

1 * RESET * 2 * RESET * 3 * RESET * 4 * RESET *

1 * RESET * 5 2 * RESET * 5 3 * RESET * 5 4 * RESET * 5

4 * RESET *

4 * RESET * 5

3 * RESET *

3 * RESET * 5

2 * RESET *

2 * RESET * 5

1 * RESET *

1 * RESET * 5

FIGURE 5 : ENERGY METERS MENU

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5.2

MiCOM M231

Settings Figure 6 illustrates the main setting menu.

SETTIN

PASSWOR

LANGUAGE

DISPLA

LOCK

PULSE OUTPU

RESET MD

DEMAND CALCULA IONS

OMMUNICA ION

CONNECTION

FIGURE 6 : SETTING MENU

Service Manual

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MiCOM M231

5.2.1

Page 15/32

Password menu Figure 7 illustrates the password menu. The user may; enter the desired level of password, cancel the current password, set level 1 password or set level 2 password. A password consists of four letters from A to Z. The ← and → keys are used to select each character in turn, whilst the ↑ and ↓ keys scroll through the available characters. To enter the password press the → key after the last character has been modified. The M231 monitors the level of entered password. If no key is pressed for 15 minutes, the password is automatically cancelled. Each level's password is the same both via the front panel and the remote communications interface. The factory-set default for level 1 and level 2 is AAAA. On receipt of the unit both levels of password should be modified to invoke password protection.

PASSWORD

ENTER PASSWORD:

ENTER PASSWORD:  A * * *

CANCEL PASSWORD:

SET L2 PASSWORD:

ENTER PASSWORD:  A * * *

SET L1 PASSWORD:

ENTER PASSWORD:  A * * *

FIGURE 7 : PASSWORD MENU

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5.2.2

MiCOM M231

Language menu Figure 8 illustrates the language menu. A level 2 password must be entered to change the language. The ↑ and ↓ keys are used to select the required language.

LANGUAGE

LANGUAGE ENGLISH

LANGUAGE: ENGLISH SET

LANGUAGE: PYCCKUN SET

LANGUAGE: SLOVENSKI SET

LANGUAGE: ESPAÑOL SET

LANGUAGE: DEUTSCH SET

LANGUAGE: FRANCAIS SET

* RUSSIAN

FIGURE 8 : LANGUAGE MENU

*

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MiCOM M231

5.2.3

Page 17/32

Display menu Figure 9 illustrates the display menu. The display settings can be modified from level 0. The desired character is chosen with the ← and → keys and its value selected with the ↑ and ↓ keys. The display's contrast may be set from 0 to 63, the backlight from 0 to 255 and the off time from 0 to 54 minutes. Display illumination is switched on with the press of any key and off after the set time from the last key pressed.

DISPLA

CONTRAST: 20

CONTRAST: 20 SET

TIME OFF: 05min

TIME OFF: 05min SET

BACK LIGHT: 255

BACK LIGHT: 255 SET

FIGURE 9 : DISPLAY MENU 5.2.4

Real time clock menu Figure 10 illustrates the real time clock menu. The real time clock can be set with level 1 or level 2 access. For time and date settings the character is chosen with the ← and → keys and set with the ↑ and ↓ keys. When setting the year, just the ↑ and ↓ keys are used.

CLOCK

TIME: 18:05

TIME: 18:05 SET

YEAR: 1999

YEAR: 1999 SET

DATE: 11.MAY

DA E: 11.MAY SET

FIGURE 10 : CLOCK MENU

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5.2.5

MiCOM M231

Pulsed outputs menu A level 2 password must be entered to set the pulsed outputs as illustrated in Figure 11. The ↑ and ↓ keys are used to select the required pulse rate. The number of pulses may be set from 20P/MWh to 1P/Wh for the real energy meter output and from 20P/Mvarh to 1P/varh for the reactive energy meter output. The pulsed outputs are derived from the displayed energy meters and their resolution will be affected by changes in the VT and CT ratios.

PULSE OUTPUT

OUT1: 100P/kWh

OUT1: 100P/kWh SET

OUT2: 100P/kvarh

OUT2: 100P/kvarh SET

FIGURE 11 : PULSED OUTPUTS MENU 5.2.6

Reset MD Menu A level 1 or 2 password is required to reset or synchronise the MD quantities as illustrated in Figure 12. To synchronise MD, reset MD since last reset or reset MD for present period, the → key must be pressed for a period of five seconds.

5.2.6.1

Synchronisation The synchronisation command operates differently depending on the selected mode of MD calculation:

5.2.6.2

•

Thermal mode - synchronisation has no effect.

•

Fixed window - at the moment of synchronisation, calculation of the dynamic MD is halted and considered for storage as the MD since reset. Calculation of MD is resumed at the beginning of the next full minute.

•

Sliding window - at the moment of synchronisation, calculation of the dynamic MD for the present sub-period is halted and considered for storage as the MD for the entire window. Calculation of MD is continued at the beginning of the next full minute of the following sub-window.

Reset MD since last reset When resetting MD since last reset the operation is performed differently depending on the selected mode of MD calculation:

•

Thermal mode - present MD and MD since last reset are reset.

•

Fixed window - MD of the window is reset and MD since last reset is reset. At the same time, synchronisation of the time interval is performed.

•

Sliding window - MD of present sub-window, all other sub-windows and MD since last reset are reset. At the same time, synchronisation of the time interval is performed at the beginning of the first sub-window.

Service Manual

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MiCOM M231

5.2.6.3

Page 19/32

Reset MD for Present Period When resetting MD for the present period the operation is performed differently depending on the selected mode of MD calculation:

•

Thermal mode - MD for present period is reset.

•

Fixed window - MD for present period is reset. At the same time, synchronisation of the time interval is performed.

•

Sliding window - MD for present sub-window and all other sub-windows in the time interval are reset. At the same time, synchronisation of the time interval is performed at the beginning of the first time interval.

RESET MD

SYNCHRONISE

SYNCHRONISE 5

MD SINCE RESET

D SINCE RESET 5

PRESENT PERIOD

PRESENT PERIOD 5

FIGURE 12 : RESET MD MENU

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5.2.7

MiCOM M231

Maximum demand calculations menu A level 2 password must be entered to set maximum demand calculations as illustrated in Figure 12. The following parameters may be set:

•

Thermal mode.

•

Fixed window - the time interval can be set between 1 to 255 minutes.

•

Sliding window - the time interval can be set between 1 to 255 minutes and the number of sub-windows between 2 to 15.

If the time interval is set to 0, the calculation of MD is switched off.

DEMAND

MD MODE:

MD MODE:

CALCULATIONS

FIXED INTERVAL

FIXED INTERVAL SET

MD MODE: THERMAL DEMAND SET

MD MODE: 1S SUD.WINDOW  SET

MD MODE: 2 SLID.WINDOW  SET

Time C.= 00 m in .

Time C.= 0 0 m in . SET

FIGURE 13 : DEMAND CALCULATIONS MENU

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5.2.8

Page 21/32

Communication Menu A level 2 password is required to set the communications parameters illustrated in Figure 13.

•

Communications rate - the communications transmission rate is selected with the ↑ and ↓ keys. The selectable rate values are 1200, 2400, 4800, 9600, 19200, and (optionally) 38400, 57600 and 115200.

•

Address - the communications address can be set in the range of 1 to 247. Address 0 is reserved for broadcast messaging.

•

Communications data form - the length, parity and stop bit can be set for the data form. The data form can be set as follows: Length:

7,8 (value 8 is always used for MODBUS RTU)

Parity:

n (none), o (odd) and e (even)

Stop bit:

1 or 2

COMMUNICATION

RS BitRATE: 19200

RS BitRATE: 19200 SET

RS ADDRESS = 033

RS ADDRESS = 033 SET

RS FRAME: 8, N, 2

RS FR ME ME:: 8, N, 2 SET

FIGURE 14 : COMMUNICATION MENU 5.2.9

Connection menu A level 2 password is required to set the connection menu as illustrated in Figure 15.

CONNECTION

CT = 00030/5

CT = 00030/5 SET

INPUT: 1b

INPUT: 1b SET

 VT = 0230.0 /230

FIGURE 15 : CONNECTION MENU

 VT = 0230.0 /230 SET

M231/EN M/B11

Service Manual

Page 22/32

5.2.9.1

MiCOM M231

CT Ratio When setting the current ratio only the primary value may be altered; the secondary value (1A or 5A) must be specified with the order. Selectable ratios are defined in Table 5. When 'set' is displayed, the character is selected by pressing the ← and → keys and the value modified by using the ↑ and ↓ keys. When the desired ratio has been selected the → key should be pressed until 'set' disappears. Ratio

Ratio Step

1A CT

5A CT

1...63

1

1...63

5...315

65...315

5

65...315

325...1575

320...630

10

320...630

1600...3150 1600...3150

650...3150

50

650...3150

3250...15750

4000

-

4000

20000

TABLE 5 : CT RATIOS 5.2.9.2

Connection input The type of connection to the power system must be set to match the physical connection implemented. The connection type is selected with the ↑ and ↓ keys. Connection types are as follows:

5.2.9.3

•

1b - single phase connection,

•

3b - three-phase, three-wire connection with balanced load,

•

4b - three-phase, four-wire connection with balanced load,

•

3u - three-phase, three-wire connection with unbalanced load

•

4u - three-phase, four-wire connection with unbalanced load.

VT Ratio Both the primary and secondary values of the VT ratio may be set. The values are set in the same manner as described for the CT ratio. When setting the voltage transformer primary value, the decimal point is also set. The decimal point is set with the ↑ and ↓ key when the decimal point is selected (underlined). By setting the decimal point, the resolution of the energy display can be changed. Voltage Range

Voltage Step

10 ... 137 V

1V

140 ... 775 V

5V

TABLE 6 : SECONDARY VOLTAGE SETTINGS Voltage Range

Voltage Step

0.1 ... 1599.9 V

0.1 V

1 ... 15.999 kV

1V

10 ... 159.99 kV

10 V

100 ... 1599.9 kV

100 V

TABLE 7 : PRIMARY VOLTAGE SETTINGS

Service Manual

M231/EN M/B11

MiCOM M231

5.3

Page 23/32

Battery The M241 is supplied with a lithium battery that is used to store setting and data in the event of a auxuiliary supply failure. This battery should last 6 years in normal operation although high temperature and humidity will shorten this time.

5.3.1

Battery replacement replacement When the battery is due to be replaced or when there has been a loss of auxiliary supply, the battery status indicator indica tor on the bottom right hand part of the front menu will flash. The M241 will remain in operation but if the battery is not replaced then the real time clock and the maximum demand measurement data will be lost in the event of a loss of the auxiliary supply.

FIGURE 16 : BATTERY STATUS INDICATOR The battery can be replaced by taking the M241 out of the panel and removing the rubber cover on the rear of the case. NOTE that removing the battery will erase all the maximum demand data values.

FIGURE 17 : BATTERY REPLACEMENT 5.4

Default settings The M231 is supplied with the following default settings. Changes to these settings to can be made on the front menu or via remote communications. Counters and registers

Set at zero

Password

None set

Language

English

Display

Contrast 20, Time off 5 min, Backlight 255

Clock

Time Zone CET, Current year and date

Demand Calculation Calculatio n

MD Mode: Thermal Demand, time constant 15 min

Communication

9600bps, address: 33, RS frame :8,n,1

Connection

VT 230.0/230 or 57.0/57 or 63.5/63.5 CT 5/5 or 1/1 Mode: 4u (3W4)

M231/EN M/B11

Service Manual

Page 24/32

6.

TECHNICAL DATA

6.1

Ratings

6.1.1

Voltage input

6.1.2

6.1.3

6.1.4

6.1.5

MiCOM M231

Nominal voltage (Un)

63.5V, 120V and 230V

Measuring range

10 to 150% Un

Burden

0); var C (if < 0)

0

var L(if > 0); var C (if < 0)

0

var L(if > 0); var C (if < 0)

0

A

0

A

0

A

0

A

0

V

0

V

0

V

0

V

0

VA

0

VA

0

VA

0

VA

0 0 0 0 0

mHz

00.000

65.535

0.001 Hz

0

mHz

00.000

65.535

0.001 Hz

0

M231/EN M/B11  Appendix Page 18/34

Service Manual MiCOM M231

Code

Address

Contents

Data

04

30068

Frequency

T1

Data

04

30069

Frequency

T1

Data

04

30070

Total power angle

T2

Data

04

30071

Phase power angle L1

T2

Data

04

30072

Phase power angle L2

T2

Data

04

30073

Phase power angle L3

T2

Data

04

30074

IN

T5

Data

04

30076

Angle 12

T2

Data

04

30077

Angle 23

T2

Data

04

30078

Angle 31

T2

Data

04

30079

30080

Average U∆

T5

Data

04

30081

30082

U12

T5

Data

04

30083

30084

U23

T5

Data

04

30085

30086

U31

T5

Data

04

30087

30088

Dynamic demand value 1

T6

Data

04

30089

30090

Dynamic demand value 2

T6

Data

04

30091

30092

Dynamic demand value 3

T6

Data

04

30093

30094

Dynamic demand value 4

T6

Data

04

30095

30096

Max demand since reset 1

T6

Data

04

30097

30098

Max demand since reset 2

T6

Data

04

30099

30100

Max demand since reset 3

T6

Data

04

30101

30102

Max demand since reset 4

T6

Data

04

30103

30104

Time stamp MD 1

T8

Data

04

30105

30106

Time stamp MD 2

T8

Data

04

30107

30108

Time stamp MD 3

T8

Data

04

30109

30110

Time stamp MD 4

T8

Data

04

30111

Time into period (minutes)

T1

Data

04

30112

U1 THD%

T16

Data

04

30113

U2 THD%

T16

Data

04

30114

U3 THD%

T16

Data

04

30115

U12 THD%

T16

Data

04

30116

U23 THD%

T16

Data

04

30117

U31 THD%

T16

Data

04

30118

I1 THD%

T16

Data

04

30119

I2 THD%

T16

Data

04

30120

I3 THD%

T16

Data

30075

Ind

Reg. Type

Service Manual

M231/EN M/B11 Appendix Page 19/34

MiCOM M231

Values/Dependencies

Min

Max

Step

Pass

mHz

00.000

65.535

0.001 Hz

0

mHz

00.000

65.535

0.001 Hz

0

0.01 deg

-180.00

+179.99

0.01 deg

0

0.01 deg

-180.00

+179.99

0.01 deg

0

0.01 deg

-180.00

+179.99

0.01 deg

0

0.01 deg

-180.00

+179.99

0.01 deg

0

A

0

0.01 deg

-180.00

+179.99

0.01 deg

0

0.01 deg

-180.00

+179.99

0.01 deg

0

0.01 deg

-180.00

+179.99

0.01 deg

0

V

0

V

0

V

0

V

0

Total active power

0

Total absolute reactive power

0

Total apparent power

0

Total I

0

Total active power

0

Total absolute reactive power

0

Total apparent power

0

Total I

0 0 0 0 0 0

0.01 %

0.00

400.00

0.01 %

0

0.01 %

0.00

400.00

0.01 %

0

0.01 %

0.00

400.00

0.01 %

0

0.01 %

0.00

400.00

0.01 %

0

0.01 %

0.00

400.00

0.01 %

0

0.01 %

0.00

400.00

0.01 %

0

0.01 %

0.00

400.00

0.01 %

0

0.01 %

0.00

400.00

0.01 %

0

0.01 %

0.00

400.00

0.01 %

0

M231/EN M/B11  Appendix Page 20/34

Service Manual MiCOM M231

Code

Address

16

40000

40001

Enter Password L1 & L2 & BP T11

A…Z

Write only

16

40002

40004

Enter Configuration Password T12

A…Z

Write only

16

40005

40006

Set Password level 1

T11

A…Z

Write only

16

40007

40008

Set Password level 2

T11

A…Z

Write only

3, 6, 16 40009

40010

Time

3, 6, 16 40011

40012

Date

6

40013

Contents

Data Ind

Reg. Type

(8)

T9

Setting

(8)

T10

Setting

Reset Counter & MD

T1

Bit-0

write only

Bit-1 Bit-2 Bit-3 Bit-8 Bit-9 Bit-10 3

40014

Calibration Voltage in V

3

40015

Calibration Current in A/10

3, 6

40016

Voltage Tr. Primaries in V/10

(4)

T1

read only

T1

read only

T1

Setting

bit # 0…13

1…15999

bit # 14…15 3, 6

40017

Voltage Tr. Secondaries in V

3, 6

40018

Current Tr. Ratio

3, 6

40019

Connection Mode

(6)

(7)

0…3 (5)

T1

Setting

T1

Setting

T1

1

Setting

9 25 5 7 3, 6

40020

Communication Settings

T1

0

Setting

1 2 3 4 5 6 7 Bit-3 Bit-4 Bit-5 Bit-6 Bit-7 3, 6

40021

Communication address

T1

1…247

Setting

Service Manual

M231/EN M/B11 Appendix Page 21/34

MiCOM M231

Values/Dependencies

Min

Max

Step

Pass 0 0 1 2 1 1

Reset Counter 1

1

Reset Counter 1 Reset pulse output Counter 1 Reset pulse output Counter 2 Synchronise MD Reset last period MD Reset MD Values 10 A/10 = 1 A

50 A/10 = 5 A

2300 for 230 V

1V

0

0.1 V

0

0.1 V

2

Unsigned integer value

1

15999

1

Unsigned exponent

0

3

1

10

775

1 V, 5 V

2

1

4000

1

2

Single phase

2

3 phase 3 wire balanced 3 phase 4 wire balanced 3 phase 3 wire unbalanced 3 phase 4 wire unbalanced 1200 baud

2

2400 baud 4800 baud 9600 baud 19200 baud 38400 baud 57600 baud 115200 baud ‘1’ => 2 stop bits; ‘0’ => 1 stop bit

‘1’ => Odd parity; ‘0’ => Ev en parity ‘1’ => Parity; ‘0’ => No parity

‘1’ => 7 bits; ‘0’ => 8 bits (read only) > 10 ms response time 1

247

1

2

M231/EN M/B11  Appendix Page 22/34

Service Manual MiCOM M231

Code

Address

Contents

Data Ind

Reg. Type

3, 6

40022

MD Setting bits # 0…7

T1

Setting

0 1…255

bits # 8…15

0 1 2…15

3, 6

(3)

40023

Counter 2 mode, bits # 0…7

T1

Bit-0

Setting

Bit-1 Bit-2 Bit-3 Bit-5 Bit-6 Bit-7 Counter 1 mode, bits # 8…15

(3)

Bit-8 Bit-9 Bit-10 Bit-11 Bit-13 Bit-14 Bit-15

3, 6

(3)

40024

Counter 4 mode, bits # 0…7 Counter 3 mode, bits # 8…15

T1

Setting

(3)

3, 6

40025

Counter 1 divider

T1

Setting

3, 6

40026

Counter 2 divider

T1

Setting

3, 6

40027

Counter 3 divider

T1

Setting

3, 6

40028

Counter 4 divider

T1

Setting

40029

40079

RESERVED

3, 6

40080

Starting current

T1

Setting

3, 6

40081

Quartz frequency correction

T2

Setting

3, 6

40082

Calibration status

T1

Bit-0 Bit-1 Bit-2 Bit-3 Bit-4 Bit-5 Bit-6 Bit-7 Bit-8

Setting

Service Manual

M231/EN M/B11 Appendix Page 23/34

MiCOM M231

Values/Dependencies

Min

Max

Step

Disable

Pass 2

Time constant (window period; interval of sub-period) Thermal function Fixed window Sliding window; # of periods Enable quadrant 1

2

Enable quadrant 2 Enable quadrant 3 Enable quadrant 4 Absolute value Inverted value ‘1’ => Reactive energy; 0 => Active energy Enable quadrant 1 Enable quadrant 2 Enable quadrant 3 Enable quadrant 4 Absolute value Inverted value ‘1’ => Reactive energy; 0 => Active energy Same as Counter 2 mode

2

Same as Counter 1 mode 1, 10, 100, 1000, 10000

(1)

2

1, 10, 100, 1000, 10000

(1)

2

1, 2, 5, 10, 20, 50, …, 50000

(1)

2

1, 2, 5, 10, 20, 50, …, 50000

(1)

2

320 for 0.2%

3 -128

I1, range HI I2, range HI I3, range HI I1, range LO I2, range LO I3, range LO U1 U2 U3

127

1

3 3

M231/EN M/B11  Appendix Page 24/34

Code

Service Manual MiCOM M231

Address

Contents

Data Ind

Reg. Type

Bit-9 Bit-10 Bit-11 Bit-12 Bit-13 Bit-14 6

40083

Calibration request

T1

Bit-0

write only

Bit-1 Bit-2 3, 6

40101

Language

T1

0

Setting

1 2 3 4 5 6 3, 6

40102

Active access level

T1

Setting

16

40110

40111

Set Energy counter 1

(2)

T3

write only

16

40112

40113

Set Energy counter 2

(2)

T3

write only

16

40114

40115

Set Energy counter 3

T3

write only

16

40116

40117

Set Energy counter 4

T3

write only

Service Manual

M231/EN M/B11 Appendix Page 25/34

MiCOM M231

Values/Dependencies

Min

Max

Step

Pass

Power angle phase L 1, range HI Power angle phase L 2, range HI Power angle phase L 3, range HI Power angle phase L 1, range LO Power angle phase L 2, range LO Power angle phase L 3, range LO Calibrate voltage inputs

3

Calibrate current inputs Calibrate phase angles English

2

Francais Deutsch Espanol Slovenski Russian Dansk Only 0 can be written

0

3

1

0

Counter 1 must be halted

-99999999

899999999

1

2

Counter 2 must be halted

-99999999

899999999

1

2

Counter 3 must be halted

-99999999

899999999

1

2

Counter 4 must be halted

-99999999

899999999

1

2

NOTE 1:

If Counter 1 or Counter 2 dividers are not set to 1, 10, 100, 1000 or 10000, then the counter does not show correct decade units (k, M, …). If Counter 3 or Counter 4 dividers are not set to 1, 2, 5, 10, 20, … then the pulse counter value will be incorrect.

NOTE 2:

The counter is halted when all quadrants are disabled (register address 40023/40024)

NOTE 3:

Example M231 Energy Counter settings

Counter

Register

Import Energy (kWh)

2/4

40023/40024

set bits 1, 2 (kWh with – sign)

1/3

40023/40024

set bits 9, 10 (kWh with – sign)

Export Energy (kWh)

2/4

40023/40024

set bits 0, 3 (kWh with + sign)

1/3

40023/40024

set bits 8, 11 (kWh with + sign)

Import Energy (kvarh)

2/4

40023/40024

set bits 0, 1, 7 (kvarh with + sign)

1/3

40023/40024

set bits 8, 9, 15 (kvarh with + sign)

Export Energy (kvarh)

2/4

40023/40024

set bits 2, 3, 7 (kvarh with – sign)

1/3

40023/40024

set bits 10, 11, 15 (kvarh with – sign)

M231/EN M/B11  Appendix Page 26/34

Service Manual MiCOM M231

NOTE 4:

All values except 0 are acceptable. The exponent (bits 14 and 15) affect the Energy Counter decimal places.

NOTE 5:

List of values for Voltage Tr. Secondary – register 40017: 10 … 137 step 1, 140 … 775 step 5. Any other value between 10 and 775 is rounded to the nearest value in the list.

NOTE 6:

List of values for Current Tr. Ratio – register 40018: 1 … 63 step 1, 65 … 315 step 5, 320 … 630 step 10, 650 … 3150 step 50, 4000. Any other value between 1 and 4000 is rounded to the nearest upper value in the list.

NOTE 7:

Connection Mode value: bit 0: set: I1 is connected; reset: I 1 is not connected (I1, P1, Q1, S1, are 0) bit 1: set: I2 is connected; reset: I 2 is not connected (I2, P2, Q2, S2, are 0) bit 2: set: I3 is connected; reset: I 3 is not connected (I3, P3, Q3, S3, are 0) bit 3: set: 3 phase balanced (P t = P1 x 3); reset unbalanced or single phase bit 4: set: 4 wire; reset: 3 wire (only for 3 phase balanced mode) At least one bit (0, 1, 2) must be set. If not, then all of them are set to 1 (value7). Bit 3 can be set only when bit 0 or bit 1 or bit 2 is set. Value 1 single phase Value 5 3u Value 7 4u Value 9 3b Value 25 4b

Note 8:

Time and Date Settings The M231 can accept invalid data. If invalid data are sent then the M231 will display and use invalid time and date. Valid data have to be ensured from application interface.

Service Manual

M231/EN M/B11 Appendix Page 27/34

MiCOM M231

7.

MODBUS DATA TYPES Registers defined in the Modbus database will define data as one of the data types described in the following table: Type

Value/Bit Mask

T1 T2 T3

T5 Bit# 31..24 Bit# 23..00 T6 Bit# 31..24 bit# 23..00 T7 bit# 31..24 bit# 23..16 bit# 15..00 T8 bit# 31..24 bit# 23..16 bit# 15..08 bit# 07..00 T9 bit# 31..24 bit# 23..16 bit# 15..08 bit# 07.00 T10 bit# 31..24 bit# 23..16 bit# 15..00 T11 T12 T16

Description Unsigned Value (16 bit) Example: 12345 stored as 12345 = 3039 (16) Signed Value (16 bit) Example: -12345 stored as -12345 = CFC7(16) Signed Long Value (32 bit) Example: -123456789 stored as 123456789 075B CD 15 (16) Unsigned Measurement (32 bit) Decade Exponent (Signed 8 bit) Binary Unsigned Value (24 bit) -3 Example: 123456*10 stored as FD01 E240(16) Signed Measurement (32 bit) Decade Exponent (Signed 8 bit) Binary Signed value (24 bit) -4 Example: - 123456*10 stored as FCFE 1DC0(16) Power Factor (32 bit) Sign: Import/Export (00/FF) Sign: Inductive/Capacitive (00/FF) Unsigned Value (16 bit), 4 decimal places Example: 0.9876 CAP stored as 00FF 2694(16) Time stamp (32 bit) Minutes 00 - 59 (BCD) Hours 00 - 23 (BCD) Day of month 01 - 31 (BCD) Month of year 01 - 12 (BCD) Example: 15:42, 1. SEP stored as 4215 0109(16) Time (32 bit) 1/100s 00 - 99 (BCD) Seconds 00 - 59 (BCD) Minutes 00 - 59 (BCD) Hours 00 - 24 (BCD) Example: 15:42:03.75 stored as 7503 4215 (16) Date (32 bit) Day of month 01 - 31 (BCD) Month of year 01 - 12 (BCD) Year (unsigned integer) 1998..4095 Example: 10, SEP 1998 stored as 1009 07CE (16) Text String 4 characters Two ASCII characters per 16 bit register Text String 6 characters Two ASCII characters per 16 bit register Unsigned value (16 bit), 2 decimal places Example: 123.45 stored as 3039 (16)

M231/EN M/B11  Appendix Page 28/34

8.

Service Manual MiCOM M231

CRC CHECKING AND GENERATING In RTU mode, messages include an error-checking field that is based on a CRC method. The CRC field checks the contents of the entire message. It is applied regardless of any parity check method used for the individual characters of the message. The CRC field is two bytes, containing a 16-bit binary value. The CRC value is calculated by the transmitting device, which appends the CRC to the message. The receiving device recalculates a CRC during receipt of the message, and compares the calculated value to the actual value it received in the CRC field. If the two values are not equal, an error results. The CRC is started by first pre-loading a 16-bit register to all 1's. Then a process begins of applying successive eight-bit bytes of the message to the current contents of the register. Only the eight bits of data in each character are used for generating the CRC. Start and stop bits, and the parity bit, do not apply to the CRC. During generation of the CRC, each eight-bit character is exclusive ORed with the register contents. Then the result is shifted in the direction of the least significant bit (LSB), with a zero filled into the most significant bit (MSB) position. The LSB is extracted and examined. If the LSB was a 1, the register is then exclusive ORed with a pre-set, fixed value. If the LSB was a 0, no exclusive OR takes place. This process is repeated until eight shifts have been performed. After the last (eight) shift, the next eight-bit byte is exclusive ORed with the register's current value, and the process repeats for eight more shifts as described above. The final contents of the register, after all the bytes of the message have been applied, is the CRC value.

8.1

Generating a CRC Step 1

Load a 16-bit register with FFFF hex (all 1's). Call this the CRC register.

Step 2

Exclusive OR the first eight-bit byte of the message with the low order byte of the 16-bit CRC register, putting the result in the CRC register.

Step 3

Shift the CRC register one bit to the right (toward the LSB), zero-filling the MSB. Extract and examine the LSB.

Step 4

If the LSB is 0, repeat Step 3 (another shift). If the LSB is 1, Exclusive OR the CRC register with the polynomial value A001 hex (1010 0000 0000 0001).

Step 5

Repeat Steps 3 and 4 until eight shifts have been performed. When this is done, a complete eight-bit byte will have been processed.

Step 6

Repeat Steps 2...5 for the next eight-bit byte of the message. Continue doing this until all bytes have been processed.

Result

The final contents of the CRC register is the CRC value.

Step 7

When the CRC is placed into the message, its upper and lower bytes must be swapped as described below.

Service Manual

M231/EN M/B11 Appendix Page 29/34

MiCOM M231

8.2

Placing the CRC into the message When the 16-bit CRC (two bytes) is transmitted in the message, the low order byte will be transmitted first, followed by the high order byte. When the CRC is appended to the message, the low order-byte is appended first, followed by the high-order byte. In ladder logic, the CKSM function calculates a CRC from the message contents. For applications using host computers, a detailed example of CRC generation is given below. Example: An example of a C language function performing CRC generation is shown on the following pages. All of the possible CRC values are preloaded into two arrays, which are simply indexed as the function increments through the message buffer. One array contains all of the 256 possible CRC values for the high byte of the 16-bit field, and the other array contains all of the values for the low byte. Indexing the CRC in this way provides faster execution than would be achieved by calculating a new CRC value with each new character from the message buffer. NOTE:

This function performs the swapping of the high/low CRC bytes internally. The bytes are already swapped in the CRC value that is returned from the function. Therefore, the CRC value returned from the function can be directly placed into the message for transmission.

The function takes two arguments: unsigned char *puchMsg;

A pointer to the message buffer containing binary data to be used for generating the CRC

unsigned short usDataLen;

The quantity of bytes in the message buffer

The function returns the CRC as a type unsigned short. 8.3

CRC generation function unsigned short CRC16 (puchMsg, usDataLen) unsigned char *puchMsg;

/* message to calculate CRC upon */

unsigned short usDataLen;

/* quantity of bytes in message */

{ unsigned char uchCRCHi - 0xFF; /* high CRC byte initialized */ unsigned char uchCRCLo = 0xFF; /* low CRC byte initialized */ unsigned uIndex;

/* will index into CRC lookup */

/* table

*/

while (usDataLen - -)

/* pass through message buffer */

{ uIndex = uchCRCHi ^ *puchMsgg++ ; /* calculate the CRC */ uchCRCHi = uchCRCLo ^ auchCRCHi (uIndex) ; uchCRCLo = auchCRCLo (uIndex) ;

} return (uchCRCHi