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2.2.2 Carefully remove the rubber band securing the flag mechanism.
2.2.3 Check that the bottom end of the contact operating card has not been dislodged
from the slot in the armature extension.
2.2.4 Check that all push-on connections to the PCB are secure.
Check that all the push-on connections to the back of the contacts are secure.
Check that all the push-on connections to terminal block are secure.
2.2.5 Carefully actuate the armature of each unit in turn with a small screwdriver/probe.
On units fitted with hand reset flag indicators, check that the flag is free to fall
before, or just as, any make contacts close.
2.2.6 Check that the serial number in the cover and the relay case match that of the
module. Replace the module in the case and refit the cover. Make sure that the
reset mechanism in the cover is correctly located with respect to the relay element
and that the flag (or mechanism) can be reset.
Check that the armature(s) are in the reset position by pressing the appropriate
reset buttons.
2.3 Insulation tests
The relay and its associated wiring may be insulation tested between:
– all electrically isolated circuits
– all circuits and earth
An electronic or brushless insulation tester should be used giving a dc voltage not
exceeding 1000V. Accessible terminals of the same circuit should first be strapped
together. Deliberate circuit earthing links removed for the tests must subsequently
be replaced.
2.4 Operate/reset operation
Warning
Exposed terminals may present a hazardous voltage unless
equipment is electrically isolated.
2.4.1 Self, hand, electrical and hand/electrical reset
The operate circuit is terminated to case terminals 27(+), 28(-). The electrical reset
circuit is terminated to case terminals 25(+), 26(-). Disconnect external wiring from
these terminals to allow application of the test supply.
With the relay reset check the continuity of the closed contacts (shown as break
contacts on the drawing).
Check operation of operate circuit and the electrical reset circuit (if applicable) by
energising the relay with 60% of the lower nominal supply voltage.
The relays should switch cleanly with one movement.
Check the operating time of the relay at 100% lower nominal supply voltage and
check the continuity of the closed contacts (shown as make contacts on the
drawing).
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