
APPLICATION NOTES
17-4
MIF Digital Feeder Protection
GEK-106273L
17.2
TRIP CIRCUIT SUPERVISION FOR M-FAMILY RELAYS
M Family relays (MIF must be option 2 to include I/O & Logic configurability) 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.
For monitoring the trip circuit while the breaker is open and when it is closed, a resistor must be added in parallel to
the 52a contact, as shown below:
Value of resistor R
Supply Ohms
Watts
48 Vdc
10 K
2
125 Vdc
25 K
5
250 Vdc
50 K
5
A9
A8
A10
TRIP
A5
A6
INP#1
INP#2
COM
TRIP COIL
TRIP
Breaker
Auxiliary
Contact (52a)
+Vdc
A9
A8
A10
TRIP
A5
A6
INP#1
INP#2
COM
TRIP COIL
TRIP
Breaker
Auxiliary
Contact (52a)
+Vdc
R
Summary of Contents for GEK-106273L
Page 19: ...GETTING STARTED 1 12 MIF Digital Feeder Protection GEK 106273L ...
Page 95: ...SETTINGS 5 38 MIF Digital Feeder Protection GEK 106273L ...
Page 101: ...I O CONFIGURATION 6 44 MIF Digital Feeder Protection GEK 106273L ...
Page 127: ...KEYPAD AND DISPLAY 8 26 MIF Digital Feeder Protection GEK 106273L ...
Page 147: ...INSTALLATION AND MAINTENANCE 10 2 MIF Digital Feeder Protection GEK 106273L ...
Page 199: ...ANNEX 5 HARMONIC FILTERING 15 4 MIF Digital Feeder Protection GEK 106273L ...