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TB XRW1-4 04.01 E
7.6
Maintenance
Maintenance testing is generally done on site at regu-
lar intervals. These intervals vary among users depend-
ing on many factors: e.g. the type of protective relays
employed; the importance of the primary equipment
being protected; the user's past experience with the re-
lay, etc.
For electromechanical or static relays, maintenance test-
ing will be performed at least once a year according
to the experiences. For digital relays like
XRW1-4
, this
interval can be substantially longer. This is because:
•
the
XRW1-4
relays are equipped with very wide self-
supervision functions, so that many faults in the relay
can be detected and signalised during service. Im-
portant: The self-supervision output relay must be con-
nected to a central alarm panel!
•
the combined measuring functions of the
XRW1-4
re-
lay enable supervision the relay functions during serv-
ice.
•
the combined TRIP test function of the
XRW1-4
relay
allows to test the relay output circuits.
A testing interval of two years for maintenance will,
therefore, be recommended.
During a maintenance test, the relay functions including
the operating values and relay tripping times should be
tested.
