Figure. 7.4 - 241. Trip circuit supervision with one DI and one latched output contact.
The trip circuit with a latched output contact can be monitored, but only when the circuit breaker's
status is "Closed". Whenever the breaker is open, the supervision is blocked by an internal logic
scheme. Its disadvantage is that the user does not know whether or not the trip circuit is intact when
the breaker is closed again.
The following logic scheme (or similar) blocks the supervision alarm when the circuit breaker is open.
The alarm is issued whenever the breaker is closed and whenever the inverted digital input signal
("TCS") activates. A normally closed digital input activates only when there is something wrong with the
trip circuit and the auxiliary power goes off. Logical output can be used in the output matrix or in
SCADA as the user wants.
The image below presents a block scheme when a non-latched trip output is not used.
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Q-M215
-M215
Instruction manual
Version: 2.04
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