Testing Of The Earth-Fault Stages; Low-Set Stage I; High-Set Stage I; Testing Of The Self-Supervision System (Irf) - ABB REJ 525 Operator's Manual

1MRS 752137-MUM
5.3.4.
5.3.4.1.
5.3.4.2.
5.3.5.
5.4.
Combined Overcurrent and Earth-Fault Relay
Operator's Manual

Testing of the earth-fault stages

Low-set stage I

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Starting
Close switch S1 and slowly increase the test current until the relay starts and
indicator L3 is lit. Read the start current value from the ammeter.
Operate time
Test according to the selected characteristics.
Definite-time characteristic
Set the test current to 2 x the the setting value of stage I
Switch off S1, clear the indicators and unlatch the output contacts. The clock is
started by closing switch S1 and stopped by closing output contact PO1.
Inverse-time characteristic
At inverse-time characteristic, the operate time is measured at two different test
current values (2 x I > and 8 x I
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those obtained from the current/time curves of the inverse-time characteristic in
question.
The test procedure is the same as at definite-time characteristic.

High-set stage I

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Starting
Close switch S1 and slowly increase the test current until the relay starts and
indicator L2 is lit. Read the start current value from the ammeter.
Operate time
Set the test current to 2 x the the setting value of stage I
Switch off S1, clear the indicators and unlatch the output contacts. The clock is
started by closing switch S1 and stopped by closing output contact PO2.

Testing of the self-supervision system (IRF)

The IRF output contact and the operation of the READY indicator LED can be
tested by selecting the function test in the HMI menu. Indicator L1 will be lit when
testing the self-supervision-system.

Spare parts

To achieve the best possible operation accuracy, all parts of the relay have been
calibrated together. Thus, each product forms a whole for which no separate spare
parts can be supplied. In case of malfunction, please consult your relay supplier.
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>). The operate times obtained are compared with
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REJ 525
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