Toshiba GRZ100 B Series, Instruction Manual

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6.5.4 Metering and Recording
The metering function can be checked while testing the AC input circuit. See Section 6.4.4.
Fault recording can be checked while testing the protection schemes. Open the "Fault records"
screen and check that the descriptions are correct for the applied fault.
The default setting of events is shown in Appendix H. Event recording on the external events such
as CB1 ready, Ind.reset, etc., can be checked by changing the status of binary input signals.
Change the status in the same way as the binary input circuit test (see Section 6.4.2) and check that
the description displayed on the "Event Records" screen is correct.
Note:
The choice of whether to record or not can be set for each event. Change the status of the binary
input signal after confirming that the related event is set to record. (The default setting enables
all the events to be recorded.)
Some of the internal events such as Trip, VTF, etc., can be checked in the protection scheme tests.
Disturbance recording can be checked while testing the protection schemes. The LCD display
only shows the date and time when a disturbance is recorded. Open the "Disturbance records"
screen and check that the descriptions are correct.
Details can be displayed on the PC. Check that the descriptions on the PC are correct. For details
on how to obtain disturbance records on the PC, see the RSM100 Manual.
6.5.5 Fault Locator
In the fault locator tests, a dynamic test set with a three-phase voltage source and current source is
required to simulate power system pre-fault, fault and post-fault conditions.
The fault locator starts measurement with one of the following tripping signals: command trip,
zone 1, zone 2 and zone 3 trip, zone 1 extension trip and external main protection trip. Therefore,
it is preferable to test it while testing the protection schemes by applying a fault.
The line parameter settings must be changed to meet those of the test set.
The measurement result is expressed as a percentage of the line length and the distance and
displayed on the "Fault Record" screen of the LCD.
Note: If abnormal settings far from actual transmission line impedance, e.g. resistance value
so larger than reactance value, etc., are done, the location error will be larger.