Commissioning Tests; Inspection; Insulation; Wiring Check - Siemens 7SG11 Technical Manual

Argus 8
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3 Commissioning tests

3.1 Inspection

Check that the relay has not been damaged in any way since being installed into the panel. Remove
the relay from the case and check that the serial numbers of the relay, the case and the relay cover are
all identical. Check also that the relay is the correct model and that the rating information is correct for
the particular installation.
Ensure that all external connections are tight and that the relay case is solidly bonded to a local earth
point by checking the earthing connection to the case. Replace the relay back into the case and check
that it is fully inserted.

3.2 Insulation

When required, insulation tests to check the relay and associated wiring can be performed using a
500V electronic insulation resistance test set. The wiring may be tested between :-
1.
All electrically isolated circuits.
2.
All circuits to earth.
Accessible terminals of the same circuit should be connected together and deliberate circuit earthing
links removed for the tests. Normal connections must be restored after testing. Satisfactory values for
the various readings above depend upon the amount of wiring concerned. Where considerable multi-
core wiring is involved a reading of 2.5 to 3.0 MΩ can be considered satisfactory. For short lengths of
wiring higher values can be expected. A value of 1.0 MΩ or less should not be considered satisfactory
and should be investigated.
We do not recommend a 2KV site pressure test on the secondary wiring with relays connected. If this
has to be carried out then, as above, deliberate earth links must be removed. Note that both the
positive and negative feeds to the relay's DC/DC converter are earthed via 5KV capacitors and the
leakage current of these capacitors may trip the 2KV pressure test set. Also note that the capacitance
effect of the secondary wiring may give rise to test set calibration errors that give impressed voltages
higher than measured. To avoid this phenomenon, the pressure test set used should have the metering
on the secondary (high voltage) side. Suitable test sets are manufactured by T&R Test Equipment
(Type KV5 – 100).
While performing the tests, HV test voltages should be smoothly increased form zero and smoothly
decreased to zero after the test to avoid arcing and trapped charge.
All Reyrolle relays are comprehensively pressure tested during manufacture.

3.3 Wiring Check

Check that the wiring to the back of the relay is as required by the external connection diagram or the
relevant scheme diagram.

3.4 Auxiliary Supply Check

Before energising the relay check with a multimeter that the dc auxiliary supply voltage is within the
operating range of the relay given in the table below :
Vaux
Vaux
Note that the relay can withstand a superimposed ac ripple of upto 12% on the upper limit of the
operative dc voltage range

3.5 Energising the Relay

If the power supply is within the correct operating range then energise the relay. Indication of correct
relay power up will be given by the green Protection Healthy LED being lit. This should be held
©2011 Siemens Protection Devices Limited
Rating (V)
24 / 30 / 48
110 / 220
.
7SG11 Argus 8 Commissioning
Operating Range (V)
18 – 60
88 – 280
Chapter 7 Page 4 of 12

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