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At least one 50GS element should be
Enabled
and configured as
Forward
or
Reverse
. This would typically
be configured to trip the circuit‑breaker. The 67GS directional element must be correctly configured to suit the
network.
Typically the test procedure is as follows:
•
Isolate the circuit and apply safety earths at both ends.
•
Apply a single phase to earth short circuit at any convenient location on the circuit.
•
Remove safety earths
•
Close the circuit‑breaker to energize the system with the primary short circuit applied.
•
Isolate the circuit at by opening the circuit‑breaker if it is not tripped already.
•
Check operation of the 50GS element and particularly 67GS
Forward
direction indication. If
Reverse
direction is indicated as the fault direction this indicates that there is a wiring polarity problem that
requires investigation and correction.
•
Apply safety earths
•
Remove the test short circuit.
•
Remove the safety earths.
Functional Tests
9.5 Direction Test of the Earth Quantities for Directional Earth-Fault Functions
412
Reyrolle 7SR5, Transformer Protection Device, Device Manual
C53000-G7040-C015-1, Edition 11.2019