Toshiba GR200 Series Instruction Manual page 81

Adjacent CB(s) tripped with Zone-trip
(iii)
Figure 2.2-9 shows a CBF Zone-trip command of the adjacent CB(s). If the target CB has failed
to clear a fault following operation of a trip relay and if the subsequent re-trip has been
unsuccessful – if this optional feature was selected – the OCCBF relay will continue to operate.
As a result, after expiration of the CBF Zone-trip time delay a CBF Zone-trip command is
issued to initiate the tripping of all other circuit breakers connected to the same busbar; the
CBF Zone-trip is completed by tripping the adjacent CB(s). Issue of the back-trip command
and the receipt of back-tripping signals by individual circuit breakers is executed through the
busbar replica. Where the protection system is associated with a feeder circuit breaker, an
initiation may also be provided to send an intertrip signal to directly connected remote circuit
breakers(s).
Fault
Fault current
Closed
Adjacent CB
Open
Unsuccessful
Closed
Target CB
Open
GEN.TRIP signal
OCCBF_CH* relay
Re-trip
Zone-trip
TCB: operating time of the target CB
TOC: reset time of the OCCBF element in CH*
Figure 2.2-9 Timing chart (Adjacent CB(s) tripped by CBF Zone-trip)
Timer set with [TCBF-RE_CH*]
Timer set with [TCBF-ZONE_CH*]
- 67 -
Unsuccessful
Centralized GRB200
(Soft: 030, 031, 032, 033, 034)
6F2S1931 (0.20)
TCB
TOC