Siemens SIPROTEC 7SS523 V3.2 Manual page 144

Functions
T-BF I<
T-BF IMP
T-BF CB fault
T-TRIP repeat
T-BF rel sup
T-BF 2chan
128
The parameter T-BF I< (XX22/CU) is used to delay for the "low-current" mode the
TRIP command and the transfer trip signal issued by the breaker failure protection.
The parameter T-BF IMP (XX23A/CU) is used to delay for pulse mode the TRIP com-
mand and the transfer trip signal issued by the breaker failure protection.
The parameter T-BF CB fault (XX24/CU) is used to delay the TRIP command and
the transfer trip signal issued by the breaker failure protection if a circuit breaker mal-
function is detected.
The parameter T-TRIP repeat (XX25/CU) is used to delay the feeder-selective rep-
etition of the TRIP command issued by the breaker failure protection.
The time for the TRIP repetition must be set to less than the delay times for the breaker
failure protection T-BF-1P (XX20/CU), T-BF-mP (XX21/CU) and for the pulse mode
T-BF IMP (XX23A/CU).
If the parameter BF BI MODE (XX14/CU) is set to with supervision, the the pa-
rameter T-BF rel sup (XX27/CU)is used to set the time for supervising the duration
of the CBF release signal.
The parameter T-BF 2chan (XX28/CU) is used to set the supervision delay during
which, counting from the initiation moment, the release signals for the breaker failure
protection must be issued.
Note
Many of the above mentioned parameters are also used for other functions such as
"Bay Unit" (Chapter 5.10, page 174).
7SS52 V4 Manual
C53000-G1176-C182-1