How to troubleshoot the screen backlight flashing on Micrologic P or H trip unit

Issue:
Screen backlight flashing on Micrologic P or H trip unit

Product Line:
Powerpact P, R and Masterpact NT, NW

Resolution:
If you are using a 2 wire system and have jumper wires to the other two terminals, 4-wire mode in the trip unit must be used when using the jumper method so that E3-E6 are all set to the Modbus protocol. When 2w+ULP is selected only E3 and E4 are set to the Modbus protocol while E5 and E6 are set to the ULP protocol.  Therefore, that when incorrect data is input into the ULP terminals the display will flash.  Set the trip unit back to 4-wire mode to fix the issue, or by removing the jumpered connection to E5 and E6 and leaving it set to 2w+ULP mode.

See attached for correct trip unit set up for various wiring schemes.

Gepubliceerd voor:Schneider Electric Belgium