Toshiba GR200 Series Instruction Manual page 21

Protection functions
Current differential protection (DIF)
(i)
GRB200 applies current differential protection for each individual bus-bar zone, which are
sectioned by the bus section and bus-coupler switches (discriminating zone protection), as well
as for the overall bus-bar system (check zone protection)
Circuit breaker failure protection (CBF)
(ii)
Phase-segregated breaker failure protection is provided in each CH and can be initiated by
either an internal or an external signal.
Fail safe (FS)
(iii)
To enhance security against false tripping due to a failure in a CT or CT secondary circuits,
the voltage check function is incorporated as fail safe feature.
End fault protection (EFP)
(iv)
This function is provided to cater for circumstances when a dead zone or blind zone is created
between the CB and the associated CT.
Command trip protection (COMTP)
(v)
Each CH receives the trip command from the MainUnit and performs tripping of the CB.
Non-directional overcurrent protection (OC)
(vi)
The function has two-stage relay elements with inverse time (IDMT) and definite (DT) time
characteristic. The function can operate non-directional characteristic in each CH.
Recording function
Fault record: The state of a fault can be recorded when the trip command is issued. It also
memorizes the fault data. On the screen, the user can see fault data with date & time, fault
phase, tripping phase, tripping mode, fault location, operating mode and power system
quantities.
Event record: can provide recording feature that memorizes any event occurred in the IED.
Disturbance record: is triggered by fault detection. The user can see the waveform
recorded by this function using GR-TIEMS.
Metering function
The following power system data is measured continuously and can be displayed on the IED
screen, and on a local or remotely connected PC.
Differential currents in three-phases in every zone

Restraint currents in three-phases in every zone

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6F2S1931 (0.20)
Centralized GRB200
(Soft: 030, 031, 032, 033, 034)