Two cables connected to mcb

[Jay89]

Evening All

Im sure this will have been discussed at some point (if so please point me to a relevant thread)

I have been to look at some remedial work where a previous inspector has flagged up on multiple circuits 'DBx Cx has two cables in mcb, need separating - C2'

These circuits are either lighting or radial power circuits supplying a small amount of sockets. All suitably rated and with decent R1+R2 readings.

I have never seen this to be worthy of a mention let alone a C2 code, i have spoken to my CPS technical and they said they cant see an issue. Just looking for anyone else's opinion

Thanks in advance!

 

[buzzlightyear]

I have been to look at some remedial work where a previous inspector has flagged up on multiple circuits 'DBx Cx has two cables in mcb, need separating - C2'

have you got eicr test certs

 

[Jay89]

have you got eicr test certs

Not to hand but yes i have seen the full EICR

 

[telectrix]

so.you have 2 radials from 1 MCB and each is suitably protected by the In rating of the MCB and Zs readings are compliant. . what's the problem

 

[buzzlightyear]

'DBx Cx has two cables in mcb

did you take pic of c/u.

 

[Octopus]

Sounds a load of bs to me.

Need more information

And you could have 10 cables in a mcb ..,

 

[Jay89]

so.you have 2 radials from 1 MCB and each is suitably protected by the In rating of the MCB and Zs readings are compliant. . what's the problem

My thoughts exactly!

 

[buzzlightyear]

if its feeding to2 radials and the appropriate mcb that should not be a problem.

 

[Jay89]

Sounds a load of bs to me.

Need more information

And you could have 10 cables in a mcb ..,

This is literally the extent of it, code 2 because as they put it two circuits supplied by one MCB.

 

[buzzlightyear]

what a load of tosh.

 

[Jay89]

if its feeding to2 radials and the appropriate mcb that should not be a problem.

Thanks, im glad you agree

 

[Midwest]

Sounds a load of bs to me.

Need more information

And you could have 10 cables in a mcb ..,

Why aren't you soaking up the sun, and drinking those lite beers the Yanks favour, instead of wasting your time on here. Holiday of a life time you said!!

 

[Midwest]

Evening All



I have been to look at some remedial work where a previous inspector has flagged up on multiple circuits 'DBx Cx has two cables in mcb, need separating -

Your EICR chaps, I don't know. What about RFC's, you got two cables in a mcb there

 

[Jay89]

Your EICR chaps, I don't know. What about RFC's, you got two cables in a mcb there

I think they're suggesting two radials rather than two cables is the issue, badly worded title. But yes the specific example they give in the OSG of taking a spur off RFC at the MCB came to mind when i saw it too.

 

[Des 56]

Your EICR chaps, I don't know. What about RFC's, you got two cables in a mcb there

2 conductor mcb for rings and 1 conductor mcb for radials ?

 

[westward10]

I would C3 it, two final circuits require individual circuit protection.

 

[davesparks]

I would C3 it, two final circuits require individual circuit protection.

It's not two final circuits, it is one, the definition of a circuit in bs7671 is very clear on this.

What basis do you have for a C3? What is the improvement that can be made? Unless this Mcb is overloaded, which is a separate matter, then nothing is improved by splitting it in to two circuits

 

[Andy78]

I would C3 it, two final circuits require individual circuit protection.

I'm not biting

 

[westward10]

I suspect this is the case of an existing circuit and then someone lashing another to it because they cannot be be bothered to employ correct installation methods by using an additional protective device at a spare way or advising the existing board has inadequate capacity.

 

[Jay89]

I suspect this is the case of an existing circuit and then someone lashing another to it because they cannot be be bothered to employ correct installation methods by using an additional protective device at a spare way or advising the existing board has inadequate capacity.

There are multiple consumer units in this EICR where it has been flagged, from what i can see most seem to be part of original installation (same cable and paired dressing). Mostly on three phase boards with no spare ways.

 

[davesparks]

I suspect this is the case of an existing circuit and then someone lashing another to it because they cannot be be bothered to employ correct installation methods by using an additional protective device at a spare way or advising the existing board has inadequate capacity.

Based on what evidence? Whilst this is possibly what has happened, there is nothing in the regulations to prevent a circuit being extended in this way.
If a radial socket circuit has the capacity for additional sockets, then why not extend it from the DB if that's the most logical place to connect it? Surely this is better than adding an additional joint into the circuit somewhere?

 

[Jay89]

I should add it has detailed labelling at each consumer unit also

 

[westward10]

See in day in day out and I will C3 it every time.

 

[davesparks]

See in day in day out and I will C3 it every time.

And which regulation do you reference to support this observation?

 

[buzzlightyear]

I should add it has detailed labelling at each consumer unit also

was the boards marked up for the
2 circuits to the mcb.

 

[westward10]

314-01-04 off the top of my head but I suspect you know this.

 

[Jay89]

was the boards marked up for the
2 circuits to the mcb.

All points supplied by that MCB yes

 

[davesparks]

314-01-04 off the top of my head but I suspect you know this.

I can't see anything in 314 to support your opinion, the closest thing is that each final circuit be connected to a separate way in a DB. There is nothing to say that a final circuit cannot comprise multiple branches from one ocpd.

 

[buzzlightyear]

reg 314.4
when an installation comprise more then one final circuit .each final circuit shall be connected to a separate way in the distribution board .

 

[davesparks]

reg 314.4
when an installation comprise more then one final circuit .each final circuit shall be connected to a separate way in the distribution board .

Yes, now add the definition of a circuit.

There is nothing which prevents a circuit being formed of two branches from an ocpd. This could be a better design if it reduces th overall length of the circuit

 

[westward10]

Old argument and my mind is not swayed, I agree with the Report the OP has but not the Coding.

 

[davesparks]

Old argument and my mind is not swayed, I agree with the Report the OP has but not the Coding.

Yes an old argument, and one where you persistently ignore the bs7671 definition of a circuit, and have yet to provide the definition of a circuit which you work to.

 

[westward10]

Yes yes yes heard all this and 314-01-04 refers to final circuit, I will not be swayed by sideway interpretations.

 

[Andy78]

Yes yes yes heard all this and 314-01-04 refers to final circuit, I will not be swayed by sideway interpretations.

You must be on a wind up quoting reg numbers from the 16th

 

[Octopus]

This is literally the extent of it, code 2 because as they put it two circuits supplied by one MCB.

I would C3 it, two final circuits require individual circuit protection.

Me thinks westward10 did the EICR.....

 

[Octopus]

Why aren't you soaking up the sun, and drinking those lite beers the Yanks favour, instead of wasting your time on here. Holiday of a life time you said!!

Yup... Very true, but there's good wifi in the parks and there's time in the queues....

It's 32 here now and we've just got back to the villa..... And I've just had a dip in the pool. It'll be beer o'clock very soon, not rubbish yank beer though....

 

[davesparks]

Yes yes yes heard all this and 314-01-04 refers to final circuit, I will not be swayed by sideway interpretations.

I don't think my interpretation is sideways, the definition of a circuit is clear, as is the regulation I think you are referring to, For the sake of avoiding ambiguity lets just call it the whole of 314.

You still have not provided any clear definition of a circuit which you are referring to, nor any clear regulation which prohibits a circuit having two branches, or two legs, being fed from the middle of the circuit, etc.

As it stands, if you were carrying out an eicr on an installation I had designed with a circuit of this nature then I think my lawyers would be ripping you a new one by now.

 

[westward10]

Final circuit, and yes I will still C3 it lawyers or no lawyers.

 

[Deleted member 9648]

Westward your argument has as much logic as the neutrals in switches argument. Some people just seem to stick their head in the sand and ignore facts.
You seem to admit that it complies with 7671 and yet insist on coding it!
You need to remember that coding can cost the occupier money, a lot of money. Unless you can justify a safety issue or a departure you CANT code.
Coding because of your personal views is simply unacceptable.

 

[telectrix]

fight ! handbags at dawn.