GEK-113308
MIWII Directional Power Protection System
C-1
APPENDIX C
C.1 TRIP CIRCUIT SUPERVISION FOR MII-FAMILY RELAYS
C
APPENDIX C APPLICATION NOTESC.1TRIP CIRCUIT SUPERVISION FOR MII-FAMILY RELAYS
MII Family relays can be used to monitor Trip circuit integrity. The circuit is basically a Voltage Monitor connected to
contact 52a. The circuit is continuously monitoring the voltage level. The circuit below is designed to monitor the complete
trip circuit. It includes the tripping coil of the breaker and the trip circuit, the wiring between the relays, and the circuit
breaker.
An alarm can be issued when the circuit is open. The figure below shows the typical wiring diagram that will provide trip
circuit monitoring while the circuit breaker is closed.
A9
A8
A10
TRIP
A5
A6
INP#1
INP#2
COM
TRIP COIL
TRIP
Breaker
Auxiliary
Contact (52a)
+Vdc