RCD and Minimum Insulation Readings

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I think the biggest problem with a borderline IR test is that whilst it might be above the tripping threshold of the RCD at the time of testing the IR won't be stable so you're almost guaranteed future problems. To be honest assuming no appliances or loads plugged in I'd consider any circuit testing <10Megs @ 250v worth investigation.

 
I think the biggest problem with a borderline IR test is that whilst it might be above the tripping threshold of the RCD at the time of testing the IR won't be stable so you're almost guaranteed future problems. To be honest assuming no appliances or loads plugged in I'd consider any circuit testing <10Megs @ 250v worth investigation.
With digital meters these days we have become paranoid with readings, with the old wind up if the handle turned easy it was clear, a quick look and over 1 meg, classed as clear and move on, it was acceptable to have 0.5 Meg on conduit install, so what is the difference between 1 Meg and 10 Meg, both are clear readings as far as required to comply. I would not waste any time trying to locate a reading of 10 Meg, but would try to find what was causing a reading close to acceptable on a new install.

If the meter had its last reading as 1 Meg and then infinity would we worry.

 
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