ABB REF615 Applications Manual page 194

Section 7
Supervision functions
188
A051097 V4 EN
Figure 91: Operating principle of the trip-circuit supervision with an external
resistor. The TCSSCBR blocking switch is not required since the
external resistor is used.
If the TCS is required only in a closed position, the external shunt resistance may be
omitted. When the circuit breaker is in the open position, the TCS sees the situation
as a faulty circuit. One way to avoid TCS operation in this situation would be to block
the supervision function whenever the circuit breaker is open.
A051906 V2 EN
Figure 92: Operating principle of the trip-circuit supervision without an external
resistor. The circuit breaker open indication is set to block TCSSCBR
when the circuit breaker is open.
1MRS756378 D
REF615
Application Manual