Earth fault loop ohms

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ADS,Only one RCD protecting whole installation!!!

Rob

That my suggestion out the window

There is an alternative way of testing Zs, if you really want a reading, but I'd be a bit curious as to why it's tripping the RCD.

I suppose if all other results are okay, then it's just one of those things - although Megger guarantee no-trip, so strange.

 

[fletchflash]

sounds wierd, i would definately want to investigate further, just calculating Zs and leaving is bad idea as clearly something wrong!

In normal circimstances the meter should never really trip on soft test. If its testing okay on other circuits and at RCD i would be inclined to test the lights again. You defo sure IR tests okay?

25mA is about normal for an RCD to trip, cheaper brands will trip even lower!

 

[sparkytim]

Have found this happens using 3 leads (as you have to on no trip test with leads) if N contact is not good.

Ze + (R1 +R2) IS acceptable result to put on test sheet.

Zs is not an essential test for RCD protected circuits, if you have proved Ze, continuity and RCD tests.

 

[Rob69]

I was wondering if it was to do with bad connections between meter probes and terminals where i am testing???

Is thier a set way to connect the test probes ie red and black first and then the green lead......could this effect the test?????

Thanks ALL

Rob

 

[Risteard]

I was wondering if it was to do with bad connections between meter probes and terminals where i am testing???Is thier a set way to connect the test probes ie red and black first and then the green lead......could this effect the test?????

Thanks ALL

Rob

For safety reasons you should connect to cpc, then neutral and lastly to line, and disconnect line first, then neutral and cpc.

 

[sparkytim]

No offense but I trust You have got the 3 leads in the right terminals on the Meter, the Black N has a special terminal at the top only used for No-trip Test, I have made the mistake myself when changeing from 2 lead testing which uses the bottom two terminals.