Siemens 7SJ82 Manual page 1376

Functional Tests
11.3 Direction Test of Ground Quantities for Directional Ground-Fault Functions
For directional testing, the Directional sensitive ground-fault detection function (67Ns) is configured and a
directional stage is switched on. For example, the directional 3I0> stage with cos φ or sin φ measurement.
The most reliable test is the one with a primary ground fault. Proceed as follows:
Isolate the line and ground it on both sides; on the farthest line end it must remain open during the
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entire test.
Place a 1-phase ground fault bridge on the line. For overhead lines, this can be done at an arbitrary loca-
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tion, in any case behind the current transformer (as seen from the busbar of the feeder to be tested). For
cables, the grounding is done on the farthest end (sealing end).
Remove the protective grounding from the line.
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Switch on the circuit breaker on the line to be tested.
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Check direction indicator (LED if routed).
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Check the indication
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direction. The indication
If backward is determined as the direction, either with the current connections or the voltage connec-
tions, there is an inversion in the neutral path. For the display
too low.
Switch the line off and ground it.
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This completes the test.
1376
(_:302) Ground fault in the ground-fault log or fault log with regard to its
(_:302) Ground fault forward must be logged as direction information.
unknown , the ground current is probably
SIPROTEC 5, Overcurrent Protection, Manual
C53000-G5040-C017-8, Edition 07.2017