It is possible to use AC voltage supply to Sepam 60 and 80 Trip Circuit Supervision?
Issue
Users may need to implement the Trip Circuit Supervision (TCS) function in Sepam Series 60 and 80 relays where the circuit breaker trip coil is supplied by 240 VAC instead of the typical DC control voltage. The question is whether the TCS function can operate correctly in this configuration.
Product
- Sepam Series 60
- Sepam Series 80
Environment
- Medium Voltage Protection Systems
- Circuit Breakers with 240 VAC Trip Coils
- Trip Circuit Supervision (TCS) Applications
- New Installations and Retrofit Projects
Cause
The standard TCS implementation in Sepam relays is generally intended for conventional trip circuit arrangements. When the trip coil is supplied with 240 VAC, the standard wiring arrangement may not be directly applicable, raising concerns about compatibility and proper supervision of the trip circuit.
Resolution
Yes, it is possible to use 240 VAC supplied trip coils with the Trip Circuit Supervision (TCS) function of Sepam Series 60 and 80 relays by implementing a special external circuit.
However, this solution should be considered an alternative implementation and requires careful design, installation, and commissioning. Because of the complexity involved and the expertise required to ensure proper operation, the Sepam team does not provide full recommendation or certification for this arrangement as a standard solution.
When applying this method:
- Ensure the special interface circuitry is implemented exactly as specified.
- Verify proper operation of the TCS function during commissioning.
- Confirm compatibility with the breaker control scheme and site requirements.
- Perform comprehensive testing to validate supervision and trip circuit integrity.
For detailed wiring information and implementation guidance, refer to the attached document containing the proposed circuit solution.