Revision Question

boltonsparky · Jul 30, 2020

Thought I'd ask on here.

It's difficult (for me at least) to determine what they're actually asking.

If they're asking max volt drop for a distribution circuit it would be 5%, 11.5V so answer a) 11.5V

But are they asking what the acceptable volt drop would be if you included the 5V they mention, so answer c) 6.5V

In my mind if you tested for volt drop at the DB, the final circuit (after your test point) with the volt drop of 5V would already be included in the test result as it is coming off the DB so the answer would be 11.5V.

I've asked elsewhere and the general consensus is c) 6.5V but I'm not convinced and it has me baffled.

I think they're tying to throw you off the scent with the 5v thing and are just asking what the max permitted volt drop for the circuit would be.

Murdoch · Jul 30, 2020

After a long hot tiring day I would say 6.5 volts

apprentice87 · Jul 30, 2020

Me too.. Very badly worded question though...

Do not forget they are taliing about verification of an EXISTING installation. If as they claim [presumably after some calculation] that the volt drop of the "worst" final circuit is 5 volts, then yes, the most you could drop up to the origin of that final circuit would be the balance of the permitted 11.5V, so the answer would be 6.5V

john..

boltonsparky · Jul 31, 2020

Cheers fellas.

I did the test today and passed, officially have my 2391 now although the certificate won't turn up for a while yet.

I'm ready for a Guinness tonight.

Murdoch · Jul 31, 2020

boltonsparky said:
Cheers fellas.

I did the test today and passed, officially have my 2391 now although the certificate won't turn up for a while yet.

I'm ready for a Guinness tonight.