Circuit Breaker Failure Protection (Cbfp); Figure 72: Logic Scheme Of Cbfp; Figure 73: Single Line Diagram, The Circuit Breaker In The Service Position - ABB UniGear Digital Commissioning And Testing Manual

AP PAR ATU S CO NTR O L T E S TI NG
5.2.2

Circuit breaker failure protection (CBFP)

The protection relay supervise trip command is processed by the Circuit breaker in the ex-
pected "tripping" time. For medium voltage the application usually uses a time delay of 300
ms. In case of a delay, the protection relay sends the tripping command to the upstream cir-
cuit breaker, typically to the Incomer and Bus tie.
It is good practice to block the CCBRBRF function if the circuit breaker is in the test or a dis-
connected position.

Figure 72: Logic scheme of CBFP

Step 1/10
Move all circuit breakers into the service position in the relative section. Check all the circuit
breakers status on the protection relay LHMIs.

Figure 73: Single line diagram, the circuit breaker in the service position

1 VLG 500 0 17 C
I NT ER LO C K S BE T W EE N PA NE LS
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