Does this comply with 314?

[Octopus]

Been at a place today.......... brand new loft conversion.......... so an additional CU has been fitted for the lights and sockets ......................

Thinking specifically about 314.2 :



I would say that it doesn't............

Opinions please

and more to the point, this conversion probably cost about £45k so using RCBO's wouldn't have been noticed................

The last one I saw was where a new single RCD board had been used for the entire house and loft conversion.............. why do people do this?

 

[Bob Geldoff1234]

I would say you are being very picky here.It only feeds the loft so the rest of the house must be on separate circuits.If you argument stood up then dual RCD boards would have to be banned.

 

[Octopus]

If you argument stood up then dual RCD boards would have to be banned.

Why?

 

[Bob Geldoff1234]

Because your saying that if the RCD trips then the power and lighting circuits will go off in the loft.Going on that principle then when a dual RCD board trips one of its RCD's then 4-5 circuits go off.Obviously this practice is still accepted as being ok otherwise the powers that be will have told us to fit RCBO's to everything as standard.

 

[Octopus]

^^ but with a dual board you would endeavor to avoid having the lights and sockets for the same room on the same RCD.

My 2nd example is more obvious - and no it wasn't TT!

I stopped fitting dual boards when the AMD3 boards were forced on us - RCBO's every time now!

 

[Phil Thompson]

But is it not that you put downstairs lights on the RCD with the upstairs sockets and visa versa. Enabling that if a trip fault occurs on 1 Circuit you still have lighting ability via the sockets in that area coming from the other RCD, which voids the dual RCD argument.

 

[Phil Thompson]

@Murdoch beat me to it.

 

[uksrevivor]

I hope thats not your safe isolation Murdoch lol

 

[Octopus]

I hope thats not your safe isolation Murdoch lol

What I was doing was in the main house - so not my "safe isolation".

FWIW the "other" CU was an older MK - with a 30Ma main switch!

If it was me I would have taken one of the other lighting circuits out of the old board and put it in the new board, then placed the new lighting circuit in the old board!

 

[uksrevivor]

I was taking mick m8 lol im still training and learning.
But agree on the point of rcbo's as it was a new loft conversion so wouldn't of cost much. Im not to keen on the fact if a fault occurs they will loose both circuits in the loft so I would of either separated them or fitted rcbo's

 

[HandySparks]

OK, I agree that RCBOs all round is 'best' and minimising inconvenience is a good thing. However, I think that the problem of being plunged into darkness is over-stated. Where I am, you're much more likely to have a power cut than an RCD trip. So, if darkness was a major safety issue, we would be installing emergency lighting to all rooms in domestic premises.

 

[Risteard]

Complete non-issue.

 

[westward10]

Green/yellow tape provides better safe isolation.

 

[Octopus]

Complete non-issue.

Why?

 

[Risteard]

Why?

Because unless you are going to argue that the Regulation requires every circuit to be individually RCD protected then it doesn't hold water. And that certainly isn't what is demanded by BS7671. Minimising inconvenience is a matter for a risk assessment - nowhere is it suggested that all possible inconvenience must be eradicated. So whilst you are entitled to your own interpretation of the Regulation I wouldn't agree with such an interpretation. If that's what JPEL/64 had wanted then presumably that's what they would have written.

 

[Davisonp]

What I was doing was in the main house - so not my "safe isolation".

FWIW the "other" CU was an older MK - with a 30Ma main switch!

If it was me I would have taken one of the other lighting circuits out of the old board and put it in the new board, then placed the new lighting circuit in the old board!

Is the “Other CU” with RCD as main switch supplying the new loft cu? No discrimination if that is the case?

 

[diditrain]

How much of the 45k, did the Electrician see though?

 

[Midwest]

If I was doing the installation for the loft conversion, I would of considered 314 and installed RCBO's.

In this install, if the RCD trips, and the occupier gets up in the middle of the night to investigate and trips over his bed pan, 'cos he's got no bed side light or room light, the installer has not done all he/she can to 'avoid danger & minimise inconvenience etc'.

So I agree with Murdoch IMO.

 

[Octopus]

Is the “Other CU” with RCD as main switch supplying the new loft cu? No discrimination if that is the case?

Split tails and Henley block

 

[Deleted member 9648]

As already stated it's a non issue.
If the end user loses the loft conversion electrics he can run a lead from elsewhere until it's fixed. If it's just nuisance tripped then the rest of the house is still on so he can see to reset.