Ductor Testing Cables?

[ACDC]

Morning all
I have been asked by my customer to carry out a ductor test on a newly installed MCC supply cable (2*300mm p/p singles supplied from a 1250a ACB)). I have told him that there is no need to carry out a ductor test on the supply cable as it is a continuous run (30m) with no joints, therefore only a INS/RES and R1+R2 would suffice. I have carried out a ductor test on the MCC bus-bars as there are multiple joints along it`s length.

So, whats your opinions guys n gals? am i right or am i wrong?

Thanks in advance

 

[Knobhead]

Test from the bar connections (not the crimped lugs) on each outgoing and incoming points. You will then get the resistance of the terminations.

If the customer wants it why argue?

I’ll take a leaf out of the tightwads book on the board “charge them extra”.

 

[Chr!s]

Morning all
I have been asked by my customer to carry out a ductor test on a newly installed MCC supply cable (2*300mm p/p singles supplied from a 1250a ACB)). I have told him that there is no need to carry out a ductor test on the supply cable as it is a continuous run (30m) with no joints, therefore only a INS/RES and R1+R2 would suffice. I have carried out a ductor test on the MCC bus-bars as there are multiple joints along it`s length.

So, whats your opinions guys n gals? am i right or am i wrong?

Thanks in advance

Well how accurate will a standard low resistance ohm meter be. If they want an accurate reading at low resistances then a ductor will provide a more accurate value.

And as Tony says, why argue, if thats what they want and they are willing to pay.

 

[Engineer54]

I guess one of the reasons why your not particually keen on doing the requested ductor tests is because you are not in possession of one. That i can understand, they are dammed expensive bits of kit for an electrician to have in his testing kit.

If that is the reason, you can always hire one out, several companies in the UK provide this service...

By the way, ....Ductor tests on new substantial switchboards and panel could be construed as mandatory. Cable terminations/connections to ACBs/MCCBs/Bus Bars, being one such area that needs to be verified, prior to being put into service...

EDIT..... Normal low resistance testing as defined in BS 7671, doesn't even come remotely close to the level of resistance measurement and accuracy a Ductor tester will perform too. Here we are talking in at most tens of micro ohms at currents of upto a 100A....

 

[Guest 004]

..........ah I see now, a microhm metre

 

[netblindpaul]

Try searching a Megger DLRO10 for an example.

 

[ACDC]

Thanks for the replies guys. We do own a micro ohm meter, just wanted to get a general opinion.
The client is tighter than a ducks arse, and we are on a tight schedule which is why i was keen just to do the standard tests.

 

[Engineer54]

Ah, ....Your working for a company then, OK, i miss read your OP, ...I was thinking that you were on your own!! lol!!! Makes a change hearing that some companies carry these very necessary bit's of kit...

Anyway should'nt take you long to conduct these tests, so long as they are pretty much readily accessible that is. ...lol!!!