Toshiba GR200 Series Instruction Manual page 36

Discriminating-zone-protection (DIFZA to DIFZF)
(ii)
In discriminating-zone-protection, the input signals are currents and the disconnector-
open/close-status (DS) signals from feeder bays, transformer bays, bus-sections, and bus-
couplers that correspond to the protection zone. The Discriminating-zone-protection issues trip
commands to all circuit breakers (CBs) within its protection-zone.
The protection-zone covered by the discriminating-zone-protection depends upon the bus-
bar configuration; the boundary of each discriminating-zone-protection is determined using
the DS signals. The user can utilize a replica setting which identifies which circuit connects to
which protection-zone; and the boundary of the zone-protection mimics the changes in bus-bar
configuration throughout the operation of the bus-bar. Up to six protection-zones are available
using the relevant input currents and DS signals.
Figure 2.1-5 illustrates input-currents and DS contacts received at respective CHs. The
input-currents are transferred to the DIFZA and DIFZB elements by the DS signal; the input-
currents are also transferred to the the DIFCH element.
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6F2S1931 (0.20)
Centralized GRB200
(Soft: 030, 031, 032, 033, 034)