Johnny vans Agnew asks this question, which concerns checking that an ELCB is working correctly, but it will not trip when tested. It has been answered by SELECT (Theme – Distribution Equipment):
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Question: I have a problem with an ELCB at one site that I am working on.
When I try to to trip the ELCB manually using the manual test button provided, it is not – in fact - tripping.
Also, it is not tripping electrically when I simulate earth leakage to the breaker. This is a problem that I have encountered with most of the ELCBs I have encountered.
What could be the cause of this?
Answer: A neutral earth wiring problem may affect the tripping and testing of a RCCB / ELCB. Note the trip test must be carried out OFF load.
If possible check the voltage between the neutral and earth points, as well as for live and neutral so as to confirm that the supply is correct.
With the device switched off, remove all load side cable. Switch the RCCB to ON and repeat the push button test. If the unit trips, this confirms that it is functioning correctly and that there is instead a load or wiring issue.
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