insulation resistane testing please help

[topcat]

Yes poor cable instulation damaged cable poor connections at switch or in the shower unit if its a electric type damp cable. loads of stuff but would need investigation as has been said are you new to testing it can take some getting your head a round hope I have helped.

 

[paulthemagpie]

would surge protective devices cause the test to show low result?

 

[Richard Burns]

SPD s can cause low line earth IR results and if they are class three can then be damaged by a 500V test since class three operate at 400V.
Make sure all sensitive equipment is removed from circuit before testing and (not according to the regs) test at 250v first, if you get a low result check the attached items again.

Neons tend to produce an IR value of about 0.1Mohms or 0.5Mohms Line to Neutral depending on type.

 

[1shortcircuit]

My most recent fault finding turned out to be a failed Fused Connection Unit.

Went down the route of "divide and conquer" found the area causing concern, disconnected terminations and results were great??? Connected accessories and tested again and fault was back. Removed accessories and tested between terminals of Fused Connection Unit and sure enough the fault was there. Replaced with new unit, retested continuity and IR and problem solved. :thumbsup

 

[ackbarthestar]

Make sure all sensitive equipment is removed from circuit before testing and (not according to the regs) test at 250v first, if you get a low result check the attached items again.

Read more: http://www.electriciansforums.net/e...tane-testing-please-help-2.html#ixzz1zknxHu00
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I think you'll find that there is a note to the IR test values where BS7671 states that 250V is permissible if you suspect that there SPDs installed.

 

[telectrix]

Examples: WATER leak, dead mouse, dead plumber.

i prefer the last one. need to test at 1000V, make sure he's dead.

 

[dagrat]

And if they are still moving after that, large lump hammer will do the trick!