OOPS
Same thing though, zero fault current for say 2.9 secs then the fault breaks down and trips the MCB.
Your theoretical view assumes a constant current flow, my practical view states that this is not often the case
Voltages between L - N - E
- Thread starter iwoot
- Start date
OOPS
Same thing though, zero fault current for say 2.9 secs then the fault breaks down and trips the MCB.
Your theoretical view assumes a constant current flow, my practical view states that this is not often the case
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I think that one of us is missing something
What I'm talking about is, in some senses, the 'best case scenario'. If, as you are suggesting, the fault current is operating the MCB despite only flowing for a very small fraction of the 2-3 seconds, then things would be 'worse' - the fault current would have to be even higher, and the 'Ze' even lower, than the figures I've mentioned - something I find hard to believe would/could be the case if (as the experiments suggest) the fault current were flowing to earth via something in the garage (be it a TT rod or bonded extraneous-c-ps).Kind Regards, John
The OP says there's a 32A breaker, not a 400A fuse, not sure where that came from.
Westie was merely using that as an example of the fact that cable faults can be intermittent (no matter what OPD the fault causes to operate, when it shows itself) - although, as I've said to him, I really don't think that is relevant in terms of the OP's problem.
Kind Regards, John
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Had the chance to check voltage in the main CU and the voltages between N-E is 0
yet when measured at bare wires at the end of the cable run its still 20v N-E
got to be something to do with the cable.
Next im going to disconnect at the JB inside to the roof where it connects to the armored cable and check there. Ground level outside is the same as roof level which is why it may sound odd.
It my parents house so i can only check when i have time which is why i cant reply sooner.
Thanks for in your input guys.
yet when measured at bare wires at the end of the cable run its still 20v N-E
got to be something to do with the cable.
Next im going to disconnect at the JB inside to the roof where it connects to the armored cable and check there. Ground level outside is the same as roof level which is why it may sound odd.
It my parents house so i can only check when i have time which is why i cant reply sooner.
Thanks for in your input guys.
So what where your Insulation Resistance results?
I am not shooting. From the fact that you hadn't done an IR measurement, I, for one, has assumed that meant that you didn't have the means to do it! Others may be asking questions more rhetorically!
Is there any way in which you could safely connect a small load (e.g. an incandescent light bulb) between L & N at the far end of the cable and then (after switching power back on!) see if the 20V N-E voltage was still there?
Kind Regards, John
No intention to do that - but the suggestion to conduct an IR test was made twice yesterday by Securespark and JohnW2 and you didn't respond - I thought you had missed the posts.
... and by westie. Never forget westie, or he might have your power disconnected
Kind Regards, John
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