Troubleshooting

SD

Supply voltage to the MN undervoltage trip release is too low or subject to significant variations

Check the power supply for the release (for example, a supply powering motors with high power ratings may be unstable). If so, connect the release to a clean or stable supply.

Supply voltage to an MX shunt trip release applied unintentionally

Check that the release connection is correct compared to the installation diagram.

SD, SDE

Operating temperature too high

Check the switchboard ventilation and the temperature in the room.

SD, SDE, SDV

Earth-leakage fault indicator (MicroLogic 4)

Information on display screen (MicroLogic 7)

Button R on VigiPacT Add-on in the out position (MicroLogic 5 and 6 with VigiPacT Add-on)

Inappropriate earth-leakage protection setting (MicroLogic 4 and 7 or VigiPacT Add-on)

Check the value of the natural leakage current.

Depending on the results:

• Isolate the equipment with excessive natural leakage current

• Or raise the earth-leakage (VigiPacT Add-on) protection setting, observing the safety rules.

Transient insulation fault on the equipment

Check whether the insulation fault coincides with commissioning an item of equipment.

Depending on the results:

• Repair the equipment

• Isolate the equipment with excessive natural leakage current

• Or raise the earth-leakage (VigiPacT Add-on) protection setting, observing the safety rules.

SD, SDE

Screen TriP (available only in MicroLogic 5, 6, and 7) then StoP

Operating temperature too high

Check the switchboard ventilation and the temperature in the room.

SD

MX shunt trip release energized

MN undervoltage trip release not energized

Check that the release connection is correct compared to the installation diagram.

OF

Circuit breaker interlocked

Check the installation and interlock diagram (mechanical or electrical) for both circuit breakers.

OF contact indicates that the circuit breaker remains open.

Close instruction not operational

Check the Auto position of the selector on the front of the circuit breaker.

Also check:

• The power supply to the motor mechanism, the motor voltage

• The voltage at the motor terminals on the motor mechanism

• The close command path

The remote command is not executed and an error code is returned by the BSCM Modbus SL/ULP module.

See returned error code described in DOCA0213••, ComPacT NSX - Modbus Communication Guide.

Depends on the error code.

Communicating motor mechanism not available

Incorrect connection between the BSCM Modbus SL/ULP module and the communicating motor mechanism

Check and connect correctly the BSCM Modbus SL/ULP module to the communicating motor mechanism.

Communicating motor mechanism not operational

Replace the communicating motor mechanism.

SDE contact permanently indicating an electrical fault

SDE adapter missing (only for ComPacT NSX100–250 circuit breakers and switch-disconnectors)

Install the SDE adapter (LV434222).

SDE adapter not operational

Replace the SDE adapter.

No SD indication communicated by the BSCM Modbus SL/ULP module

SD auxiliary contact for BSCM Modbus SL/ULP module with commercial reference LV434210 or NSX cord missing

Connect to the BSCM Modbus SL/ULP module:

• the SD auxiliary contact for BSCM Modbus SL/ULP module if the BSCM Modbus SL/ULP module is in Modbus SL only mode

• or the NSX cord if the BSCM Modbus SL/ULP module is in ULP only mode or in Modbus SL and ULP mode.

Incorrect connection between the BSCM Modbus SL/ULP module and:

• the SD auxiliary contact for BSCM Modbus SL/ULP module with commercial reference LV434210 if the BSCM Modbus SL/ULP module is in Modbus SL only mode

• or the NSX cord if the BSCM Modbus SL/ULP module is in ULP only mode or in Modbus SL and ULP mode

Check that:

• the red marker dots match.

• there is no loose contact or wiring issue.

SD auxiliary contact for BSCM Modbus SL/ULP module or NSX cord not operational

Replace:

• the SD auxiliary contact for BSCM Modbus SL/ULP module (when the BSCM Modbus SL/ULP module is in Modbus SL only mode)

• or the NSX cord (when the BSCM Modbus SL/ULP module is in ULP only mode or in Modbus SL and ULP mode).

Screen TriP then StoP

Serious detected fault on the MicroLogic trip unit: the trip unit can no longer provide protection

Change the trip unit urgently.

The circuit breaker cannot be reset.

Screen Err

Detected fault on the MicroLogic trip unit

Change the trip unit on the next maintenance visit.

The trip unit can still provide protection.

Screen Out

Acknowledgment of a latching alarm which has not been reset on the SDx module

Check the cause of the alarm and use the OK button to carry out the reset.

Several Modbus servers not communicating with the client

More than one Modbus server has the same Modbus address.

Set each Modbus server with a unique Modbus address.

The BSCM Modbus SL/ULP module is not communicating with the Modbus client.

BSCM Modbus SL/ULP module not powered

Check the BSCM Modbus SL/ULP module power supply.

Incorrect wiring between the BSCM Modbus SL/ULP module and the Modbus SL hub

Check the wiring of:

• The BSCM Modbus SL/ULP module.

• The Modbus SL hub.

BSCM Modbus SL/ULP module with Modbus parameters different to the Modbus client parameters

Check that the BSCM Modbus SL/ULP module is set with the same parameters as the Modbus client parameters.

BSCM Modbus SL/ULP module not operational

Replace the BSCM Modbus SL/ULP module. Refer to the ULP LED status.

None of the BSCM Modbus SL/ULP modules connected to the same Modbus SL hub are communicating with the Modbus client.

Modbus SL hub not operational

Replace the Modbus SL hub.

No data from MicroLogic 5, 6, or 7 trip unit is available.

Incorrect wiring between the BSCM Modbus SL/ULP module and the MicroLogic 5, 6, or 7 trip unit

Check the wiring between the BSCM Modbus SL/ULP module and the MicroLogic 5, 6, or 7 trip unit.

ULP modules are not communicating with the BSCM Modbus SL/ULP module.

BSCM Modbus SL/ULP module not powered

Check the BSCM Modbus SL/ULP module power supply.

Incorrect wiring

Check the wiring of:

• The BSCM Modbus SL/ULP module.

• The ComPacT NSX circuit breakers.

• The NSX cord.

• The MicroLogic 5, 6, and 7 trip units.

BSCM Modbus SL/ULP module not operational

Replace the BSCM Modbus SL/ULP module. Refer to the ULP LED status.

NSX cord not operational

Replace the NSX cord.