3 Electricians 4 Opinions

[Chris Holmes]

Hi All,

I know of 3 houses which have recently had additions to their Electrics...?..

In the case of our house our thoroughly useless and I suspect unqualified "sparky" insisted that the MCB for the lighting circuit he had extended must be put on the RCD side of the CU before he could sign off the jb and give us a certificate (he then failed to buy the necessary busbar to do this (I got my own electrician to swap all the lighting MCBs for RCBOs) and eventually got the certificate (The BCO said the only bit he was bothered about was the extractor fan in the bathroom).

My Brother's girlfriend had an outside security light fitted and the sparky said he couldn't do it unless she got a new CU and specified one (but the quote didn't detail whether it had a number or RCDs or RCBOs or what (I presume it must have had one or t'other).

My Brother then had a new kitchen and the suppliers insisted on fitting a new circuit or two (I assume they uprated the cooker circuit). He has also recently had a couple of outside lights replaced.

I was rather disappointed* to find that he still has his original CU (All MCBs and I can't spot even 1 RCD in the house).

I know that there is no (or was) no requirement for an older house to meet current regs (I suppose I may have just answered my own question there).

But it would it be the case that when professionals are involved, at least the circuits they work on / install should be RCD / RCBO protected.

*This is a man who believes that 3 way 13A block type adapters are dangerous and must never be used and wouldn't believe me that running a 4 way off a way was ok if the second only had a BT Home Hub, a Hive box and a DECT phone hanging off it. And has spent a fortune on windows, doors, a porch, a kitchen, etc, etc but won't update the CU unless he's held at gunpoint!

Anyways, to my question...?

Do any of the above scenarios mandate the fitting of RCDS / RCBOs?

[John Rumm]

While it is true that there is no requirement to bring properties that are inline with previous versions of the regs up to modern spec, one does have to do all new work to the regs in force at the time.

So for example, if adding a socket to a non RCD protected circuit, you would need to either provide RCD protection for just that socket, or retrofit it for the whole circuit. There would obviously be safety benefits to the latter approach in some cases.

With the 18th edition RCDs are pretty much unavoidable on most circuits, since all sockets now need them, and the cable protection requirements mop up most of the others. Moving forward, all RCBO installs are the sensible way forward for all but the most budget installs IMHO.

[George Miles]

When I bought this house it had fuse wires in a wooden box and ancient rubbery wiring. My first move was to get an electrician to fit 3 beefy radials with a socket at the ends for electric heaters etc in the most used rooms. They added a new consumer unit and a new earth spike, presumably they wanted nothing to do with the old wiring. [george]

[Scott]

On Tue, 20 Oct 2020 12:43:03 +0100, John Rumm [e-mail] wrote: [snip]

A few years ago I asked an electrician to fit the full set of RCBOs. He said this would be far too expensive and unnecessary. I asked him to get me a price and he came back and said it cost less than he had expected. I told him to go ahead, which he did. He ultimately conceded this was the 'way to go'.

[ARW]

All of them if done to the latest rules. Although the outside light at your sisters could in theory be fed from a RCD fused spur.

[Alan]

There have been debates about this on the IET site since the 18th came in. The opinion is that RCD fused spares are now not allowed,on their own, as BS7288 says they need additional protection before the device. In real life terms, a fused spur would be fine, but the Committee doesnt seem to think it is enough, but havent explained their reasoning. I've not looked into it recently, 2 links here from last year going into more detail.

[Roger Hayter]

Having read that, do you think an RCD/FCU to replace an existing FCU would count as a minor alteration rather than a new circuit? If not, a plug in RCD using an existing socket would be totally outside the scope of the wiring regs?

[ARW]

They were talking about that in the 17th edition.

[Algernon Goss-Custard]

Can't see anything there about fused spurs.

[ARW]

That's not my problem.