Figure. 7.2 - 211. Application example and its connections.
7.3 Trip circuit supervision (95)
Trip circuit supervision is used to monitor the wiring from auxiliary power supply, through the IED's
digital output, and all the way to the open coil of the breaker. It is recommended to supervise the health
of the trip circuit when breaker is closed.
Trip circuit supervision with one digital input and one non-latched trip output
The figure below presents an application scheme for trip circuit supervision with one digital input and a
non-latched trip output. With this connection the current keeps flowing to the open coil of the breaker
via the breaker's closing auxiliary contacts (52b) even after the circuit breaker is opened. This requires
a resistor which reduces the current: this way the coil is not energized and the relay output does not
need to cut off the coil's inductive current.
A
AQ
Q-T215
-T215
Instruction manual
Version: 2.04
353
