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Immediately after receiving the relay, the customer should perform a visual check and
perform the acceptance tests in this chapter to ensure the relay has not suffered
transportation damage and that the factory calibration has not been altered.
These tests can be performed as installation or acceptance tests in accordance with
user criteria. Given that the majority of users utilize different procedures for installation
and acceptance tests, this section includes all of the necessary tests that may be
performed with these relays.
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Verify that the data on the nameplate coincides with the data from the order.
Disassemble the relay and check that the parts have not been broken or damaged during
transportation.
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All devices that are powered by alternating current are affected by the frequency.
Because a non-sine wave is the result of a fundamental wave and a series of harmonics
belonging to this fundamental wave, the devices that are powered by alternating current
are affected by the form of wave applied.
To correctly test relays that operate on alternating current it is necessary to use a
voltage and/or a current sine wave. The purity of a sinusoidal wave (absence of
harmonics) cannot be expressed specifically for any given relay. However, in any relay
that includes tuned circuits, circuits R-L and R-C are affected by the non-sine waves as in
the case of the TOV relay.
These relays respond to the voltage waveform differently from the majority of
alternating current voltmeters. If the AC source used for the test contains many
harmonics the voltmeter and the relay readings will be different.
The relays are calibrated in the factory using a network of 50 or 60 Hz containing a
minimum amount of harmonics. When testing the relay, you should use an AC source
whose waveform does not contain harmonics.
The voltmeters and chronometers used to perform trip tests and operating time must
be calibrated and their precision should be better than that of the relay. The network
power used in the tests must remain stable, mainly in the levels near the pickup voltage.
GEK-98834B
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