Recording Function - Toshiba GRT100 Series Instruction Manual

3.4 Recording Function

The GRT100 is provided with the following recording functions:
Fault recording
Event recording
Disturbance recording
These records are displayed on the LCD of the relay front panel or on the local or remote PC.
3.4.1 Fault Recording
Fault recording is started by a tripping command of the GRT100 or PLC command by
user-setting (max. 4) and the following items are recorded for one fault:
Date and time of fault occurrence
Operating phase or fault phase
Tripping command
Tripping mode
Power system quantities
Up to the 4 most-recent faults can be stored as fault records. If a new fault occurs when 4 faults
have been stored, the record of the oldest fault is deleted and the record of the latest fault is then
stored.
Date and time of fault occurrence
The time resolution is 1 ms using the relay internal clock.
To be precise, this is the time at which a tripping command has been initiated, and thus it is
approximately 10 ms after the occurrence of the fault.
Operating phase or fault phase
The operating phase or fault phase can be selected.
The operating or fault phase is determined by differential element (DIFT) and high-set
overcurrent element (HOC) operating phase.
The fault phase recording is available when the primary winding of the transformer is
star-connected. However, the operating phase recording is recommended in case of a star-delta
power transformer because the fault phase at the delta-winding side cannot be recorded.
The fault phase is expressed taking that of primary winding as a reference phase.
Tripping command
The tripping output relay(s) operated is shown in terms of number (e.g. TP-1: 1, TP-2: 2 etc.).
Tripping mode
This shows the protection scheme that initiated the tripping command.
Power system quantities
The following power system quantities in pre-faults and faults are recorded.
(However, the power system quantities are not recorded for evolving faults.)
 61 
6 F 2 S 0 7 8 9