Does this setup contravene any regs or is it ok?

[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.

 

[elsparko]

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 -

View attachment 43990

not allowed pics mate, westward will have a wobbly

 

[elsparko]

tell the assessor to come back round and rub his nose on the mcb till he understands hes wrong

 

[Nigel]

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.

I think the intent of 314.4 is to not link two circuits together downstream so that say the ground floor lighting is not linked to the upstairs lighting when protected by seperate OCPDs. This could cause an issue when isolating safely. It would also cover borrowed neutrals.

I think the interpretation that it means each final circuit must have an independant OCPD is a red herring.

 

[Deleted member 26818]

The Reg states final circuit which also has a definition.

Don’t think the definition of a final circuit would have any bearing on the matter?

 

[Nigel]

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.

I think the intent of 314.4 is to not link two circuits together downstream so that say the ground floor lighting is not linked to the upstairs lighting when protected by seperate OCPDs. This could cause an issue when isolating safely. It would also cover borrowed neutrals.

I think the interpretation that it means each final circuit must have an independant OCPD is a red herring.

 

[Deleted member 26818]

I think the intent of 314.4 is to not link two circuits together downstream so that say the ground floor lighting is not linked to the upstairs lighting when protected by seperate OCPDs. This could cause an issue when isolating safely. It would also cover borrowed neutrals.

I think the interpretation that it means each final circuit must have an independant OCPD is a red herring.

Interpretation?
The definition of a circuit states: “protected against overcurrent by the same device(s)”.

 

[Nigel]

Interpretation?
The definition of a circuit states: “protected against overcurrent by the same device(s)”.

I am unsure of the relevance of this post to mine.

 

[Deleted member 26818]

I’m not sure what it is you mean when you state this:
“I think the interpretation that it means each final circuit must have an independant OCPD is a red herring.”

 

[Nigel]

I’m not sure what it is you mean when you state this:
“I think the interpretation that it means each final circuit must have an independant OCPD is a red herring.”

Some people’s arguement is that to connect two final circuits to the same MCB is a contravention to Reg 314.4.

I think that is not the intention of that reg.

 

[The Ghost]

I imagine he would have conniptions if he (assessor) saw some of the multi light circuits and RFC with comms sockets connected at MCB that I regularly see then. I can't see why the loft light was not put up on the upstairs lighting in the first place. Someone wasn't thinking, one light on a 6a MCB could be argued to be not taking account of the sections referred to in 314.x.x i.e. OCPD. I can't see any of the stipulations from i-iv have been breached though. But it is very on the "raggedy edge" arguing the point. So the assessor could be asked what he makes of OCPD for one LED light (4-7w) 7/230 =0.03 A, does that make sense?