Does this setup contravene any regs or is it ok?

[Wilko]

How would you record Zs etc on the cert with two finals coming from one MCB?

Wouldn't you find the largest value and use that. Same as if the circuit was made by a MF junction box a few metres away from the board (?).
Edit - apologies to others whose idea I appear to have nicked - should've read the replies before sprouting off. I will do better, I promise.

 

[Wilko]

I had a polite rebuttal for the Assessor's argument too, but for some reason the webby has deleted it. Perhaps it's the start of a reversal of all the double posts? So I'll stick with a pic -

 

[Wilko]

I’ve just done a large job where I fitted a double stack board (23 ways) and by the time I’d finished we only had two spare ways left in the board. So I thought that I’d free up one more by moving the lighting circuit for the loft on to the lobby lighting circuit at the CCU so both circuits are now on the one 6A MCB. Other than that they are totally separate. They also only contain one light for the loft and two lights for the lobby (all LED’s)

To me this is no different from taking the supply from the last lobby light to the loft and actually might make it easier to find a fault if you could separate it at the board rather than mess about behind down lights.

All was good until I decided to use this job for my Stroma visit.....
I was told that in no way can I do this and I need to correct it or it will go down as a non conformity. After arguing the point for 10 minuets I gave in and put the other MCB in and moved the loft light on to its own circuit and all was peaceful again.

Who’s right here?

Well he's not right in my humble opinion . Maybe he couldn't find anything to talk about, and some folks are not happy to be happy (won't say who ...).

 

[westward10]

I like an assessor who knows his stuff.

 

[SparkyChick]

I like an assessor who knows his stuff.

Good practice aside (although it could be argued as @Wes1000 pointed out that by having two cables at the CU allows for easier fault diagnosis - providing they are properly labelled they can be split, separating the lobby and attic), how does it contravene the regulations?

I'm not trying to be a smart a$$, if it breaches the regs, I'd like to know which ones and understand why.

 

[Midwest]

I like an assessor who knows his stuff.

Yeah, but this one doesn't perhaps

I'm just reading the bit about (what Murdoch said) an unfused spur in App 15 (informative) RFC & Radials. It says 'An unfused spur may be connected to the original of the circuit in the distribution board'?

 

[Pete999]

Yeah, but this one doesn't perhaps

I'm just reading the bit about (what Murdoch said) an unfused spur in App 15 (informative) RFC & Radials. It says 'An unfused spur may be connected to the original of the circuit in the distribution board'?

Good practice aside (although it could be argued as @Wes1000 pointed out that by having two cables at the CU allows for easier fault diagnosis - providing they are properly labelled they can be split, separating the lobby and attic), how does it contravene the regulations?

I'm not trying to be a smart a$$, if it breaches the regs, I'd like to know which ones and understand why.

Ask the STROMA guy to put his comments in writing, to enable you to send them to the IET, CERTSURE etc for confirmation and the reg number, and watch his bottom go sixpence, shilling half a crown, "note possibly not understood by the younger members of the forum"

 

[Wes1000]

He is correct and has backed it up with a Reg number.

How would you record Zs etc on the cert with two finals coming from one MCB?

He didn’t provide a reg number, that was just the only one I could really find that remotely resembles what he was blithering on about.

Like others have said, I record the highest Zs and R1+R2 but now have to alter the results with another circuit.

Thanks for all the reassurance guys and gals. It’s good to know I wasn’t wrong.

 

[westward10]

Good practice aside (although it could be argued as @Wes1000 pointed out that by having two cables at the CU allows for easier fault diagnosis - providing they are properly labelled they can be split, separating the lobby and attic), how does it contravene the regulations?

I'm not trying to be a smart a$$, if it breaches the regs, I'd like to know which ones and understand why.

The assessor may have been considering Reg 314.4.

 

[telectrix]

Wonder what the assessor would have made of a RFC, with a spur from the CU then ??

he'd probably have choked on the brown envelope, trying to eat the evidence.

 

[Midwest]

The assessor may have been considering Reg 314.4.

Think he's right out on the raggedy edge on that one. Why would it matter if the loft light went out with the hall one, even if they were both habitable rooms? Grd floor & 1st floor, I could understand.

 

[Midwest]

he'd probably have choked on the brown envelope, trying to eat the evidence.

Sssshhh, you may get deleted, we're discussing a seriarse matter here.

 

[Wilko]

Where's @elsparko? Would've been settled with an arm wrestle, move on.

 

[Deleted member 26818]

This is one of those rare times that BS7671 contradicts it’s self.
On the one hand we have a Regulation telling us each circuit must be connected to a separate way at a DB.
Then on the other hand we have a definition telling us that however many circuits we connect to a separate way, they all become one circuit by virtue of being fed from the same origin and being protected by the same OCPD.

 

[westward10]

The Reg states final circuit which also has a definition.