ELCB-v and readings with earth loop meter
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ericmark
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Location: Llanfair Caereinion, Mid Wales.

ELCB-v and readings with earth loop meter

by ericmark » Fri Jul 27, 2012 7:24 pm

I am a young one only 61 so did not do much with the old voltage ELCB. I have come across one and since often in fact I intend to do it they are left in circuit as an isolator.

So finding one I was wondering if still in circuit. Since there was also a 30 ma RCD I expected it was no longer used as a ELCB-v however I returned armed with my earth loop impedance tester just in case.

Well the "Wiring incorrect do not proceed" lamp came on. I used a wandering lead to earth wire and it allowed me to proceed. Clearly line and neutral were correct it was an earth problem. 35 ohms to earth wire but although everything seemed to be connected correct after the ELCB-v there seemed to be no earth or at least around the 800 ohm mark.

The consumer unit and ELCB-v must have been installed by a midget as I can't get into the space. The owner at 7' has no chance. Clearly I need to fit earth rods and extra RCD's where not already covered but wonder what is the resistance of a ELCB-v? Is it the ELCB-v which is causing the high reading or have I got something disconnected?

At 61 and 6 foot tall I just can't crawl into the spider filled aperture where the meter is fitted. Neither can the owner at 79 years old and 7 foot tall. So could the ELCB-v be the cause of the high ELI or do I need to look else where?

At 61 just not old enough to remember these units seen them before yes but not armed with an earth loop impedance meter.

Failing some reply I intend to use the heavy hand and knock in new earth rods and fit new RCD's but pure interest would like to know if the ELCB-v is the cause of high readings.

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