Trip Circuit Supervision Relay
Working principle and connection diagram.

  1. Trip circuit supervision relay.
  2. Connection diagram of TCS relay.
  3. Working principle.

1 - Trip circuit supervision relay:

Trip circuit supervision relay: basic principle and diagram

The trip circuit supervision relay is a monitoring relay and it is known as numerical name 96 S. it is used for continuous monitoring of breaker trip circuit healthy or not healthy in HT panel in any premised or substation. If the trip circuit will not ok then it will provide an alarm for avoiding any fault.
In an electrical panel trip circuit of the circuit breaker is critical. During fault conditions If the trip circuit did not find any trip sensing then the breaker will not be disconnected and the resultant by this problem may be a very loss.
So, keeping the trip circuit healthy the TCS relay is used so that system always remains healthy.
The trip circuit supervision relay is used in the HT panel for continuous monitoring of breaker trip circuit healthy. If the circuit is not healthy or abnormality in the trip circuit then it will activate to alarm.

The reason may be Trip circuit for unhealthy:

Many contacts are connected in series along a trip circuit of an electrical circuit breaker.

  • Loss of breaker auxiliary supply.
  • Low gas pressure in SF6 breaker.
  • Abnormal vacuum pressure in VCB.
  • Trip circuit supervision relay also may be faulty.

2 - Connection diagram of trip circuit supervision relay.

Trip circuit supervision relay: circuit diagram and working principle.

3 - Working principle of TCS relay.

TCS relay working principle has many important points given below mentioned.

  • Monitoring the complete trip circuit of the circuit breaker.
  • Identify the faults in the supervised circuits, like the not available voltage, the circuit to be open, contact flashing in connections, and resistance abnormal in wires, contacts, and trip coils.
  • C. Low-level measuring current enables application in sensitive or high resistance circuits.
  • False signals are avoided for circuit breaker smooth operations.
  • Operation indication by a single dual-color LED Complete range of rated voltages either AC or DC.
  • Galvanic isolation is possible between auxiliary source and supervised circuit Very low burden on the auxiliary source.

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