Setting The Generating Set Differential Protection - SDMO R33C3 User And Maintenance Manual

Setting the generating set differential protection

4.2.2.4.
The setting of the generating set's residual current device is guaranteed by a differential relay fitted near the control unit (type A / AC or
B depending on the generating sets). As a result, two parameters relating to the downstream device (terminal circuit) must be set:
- Current threshold: the generating set's differential relay must be three times more sensitive than that of the terminal circuit.
- Time delay: the cut-off of the generating set's differential relay must be longer than that of the terminal circuit.
- Type A / AC differential relay:
Use:
Differential relay for which operation is guaranteed:
•
for residual sinusoidal alternating currents;
•
for continuous pulsed residual currents;
•
for continuous pulsed residual currents with a continuous component of 0.006 A with or without phase check,
independent of the polarity.
Setting:
1. Use a screwdriver to set the current
threshold potentiometer (1) to 0.03 A (30
mA).
2. Use a screwdriver to set the time delay
potentiometer (2) to 0s (automatic).
3. Test the residual current device using the
"Test" button on the relay (3).
Current threshold potentiometer
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Test Button
(3)
Time setting potentiometer
(2)
(1)