Earth Loop Impedance Fault

[pwhitworthpafc]

Hi folks.

First post, but need some pointers.

Trying to complete a test on an empty property (to return to Housing Associatin)

1. Measured incoming Voltage at CU was 194V. Unable to complete loop/Zs/RCD tests (no probs I thought ..meter, kewtech kt64, not playing cause the supply V is too low.

2. Distribution company checked it out and reported incoming V of 237V.

3. Revisited today. V at main switch = 222V.

However open switch and it goes up to 230V+

4. And....Meter indicates earth is present, but when trying to measure Ze with main switch open I'm getting >1999 ohms.

With switch closed I'm getting "N - PE Hi V" (E-N fault?)...this still doesn't explain the >1999.

Am I missing something simple or could there be a suppliers meter fault

Thanks in advance

 

[Sidewinder]

What is the incoming supply type?

 

[pwhitworthpafc]

What is the incoming supply type?

Sorry..TN-C-S

 

[steptoe]

when you are measuring the voltage,

what is it in regards to?  P-E or P-N ?

have you checked for reverse polarity?

 

[pwhitworthpafc]

Polarity is correct.

With the KT64 (3 wire method) the lcd screen indicates if polarity is reversed or if no earth present.

Which is confusing me as to why the loop test shows >1999ohms (as you'd expect if the earth was missing)

Yet close the main switch and it indicates high E-N voltage and will not carry out the test

 

[steptoe]

Where have you measured voltage?

Do you have h dropped neutral somewhere?

That would give a N-E voltage .

 

[zimmy]

Measure voltage between line and earth, then line and neutral.  What is result.

If you have identified the line conductor and cannot get a Ze result then you have no viable earth path.  Some meters pre-test but this reads 'ok' at very high values' DO NOT DEPEND ON THIS as an indicator to a valid path.  I think there is no valid earth path at the mains.