Change of use of circuit- RCD ot not?

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Nov 28, 2009
Messages
14,681
Reaction score
832
Here's an interesting one.

Customer wants me to remove 5 storage heaters.

In their place he wants 5 single 13A sockets.

DNO has already been and changed the meter to a single rate meter, and has re energised the former off peak CU on a permanent supply already.

Each storage heater is a radial circuit protected by a 15A MCB wired in 2.5 t&e

Old style Wylex consumer unit with no RCD.

At each heater point I would be changing the existing 20A DP switch that fed each heater with a single 13A single socket.

I would not be changing the MCB or indeed making any alterations whatsoever to the CU.

New use would be no greater load than the old use feeding the heaters.

So does this count as a "new" circuit, in which case it needs an RCD (which realistically means a CU change), or can I just proceed.

Certainly a grey area and I can't decide which.

 
Oh good question, I will watch the answers, as I don't know, what about just fitting a RCD on the feed to the board?

 
i would think the sockets need rcd protection as they previously fed fixed indoor appliances and now are general use sockets that may be used for outdoor equipment

 
i would think the sockets need rcd protection as they previously fed fixed indoor appliances and now are general use sockets that may be used for outdoor equipment
None of them would be closer to a door then any existing sockets, so unlikely to be used for outdoor stuff.

 
Dave, why not retro fit an MCB into the board and install a stand alone 30mA RCD before the main switch to the board?AndyGuinness
The board is not that old. It already has old style MCB's, it just doesn't have an RCD.

Fitting a stand alone RCD is to messy.

I've done some searching and found that RCD incomers for those old boards are readily available and very cheap.

So what I will do is replace the switch incomer on the old off peak board with an RCD before converting it to socket outlets. I will also suggest to the owner that to make the installation safer, that I also replace the incomer on the main board with an RCD, even though i'm not touching that so have no need to.

It would still be interesting though to see the opinion of the forum whether it would be okay to change the use without an rcd or not.

 
Last edited by a moderator:
I've done several of these strip out storage heaters and convert to socket jobs. If the cu is old I replace with an RCD board. If it's newer I replace the main switch for an RCD incomer. If the whole installation is old and the two boards are adjacent to each other I will sometimes recommend to the client to have a new large board incorporating all the circuits in one new board. In one job where storage heaters on E7 were being replaced by Panel Heaters I left the circuits without RCD protection as only the heaters and tariff were changing but not the 20 amp switches and nothing could be plugged into them.

 
To my mind these are new circuits even if they are reusing old cables and any wiring needing RCD protection under 7671 will still need an RCD along with being notified to LABC (as new circuits).

 
RCD sockets maybe, if the customer doesnt mind the slight extra cost.

 
Defo rcd the sockets or like you said the whole board bum coverage complete !!

I would say a change of use is a good as a new circuit providing all tests result satisfactory.

 
The end of last week, I had a few jobs to complete in a flat which was part of a very old house. The customer wanted extra sockets fitted (do you remember the weird bedroom thread with the bloke asleep whilst i was working!)

Well there were some newish looking single sockets, not brand new but say about 2 years old for arguments sake. When I initially went to quote for the work, I found that none of the single sockets worked.

Customer said they used to be on economy 7 and when they told the supplier they wanted single rate tariff then when they came and removed the meter that is when the sockets stopped working.

There was only a standard consumer unit in the flat, but when I checked the incomming supply and metering by the communal front door, there was an old bakelite switch, no fuses and the twin and earth cables cut and hence the sockets no longer working in the flat.

They used to have a spanish friend electrician, so I wonder if he wired it up for them years ago:C

 
I would say that as you are not installing the cabling then that would not need RCD protection, however all socket outlets under 20A do require RCD protection under BS7671:2008(2011) and as this is not a "like for like" change they will be new sockets and therefore fall under this reg.

Another question that this leads to,,, if this job weren't in Scotland, would this need notifying?

 
Here's an interesting one.Customer wants me to remove 5 storage heaters.

In their place he wants 5 single 13A sockets.

DNO has already been and changed the meter to a single rate meter, and has re energised the former off peak CU on a permanent supply already.

Each storage heater is a radial circuit protected by a 15A MCB wired in 2.5 t&e

Old style Wylex consumer unit with no RCD.

At each heater point I would be changing the existing 20A DP switch that fed each heater with a single 13A single socket.

I would not be changing the MCB or indeed making any alterations whatsoever to the CU.

New use would be no greater load than the old use feeding the heaters.

So does this count as a "new" circuit, in which case it needs an RCD (which realistically means a CU change), or can I just proceed.

Certainly a grey area and I can't decide which.
Well additional protection is required for socket outlets, so where socket outlets are being installed, then RCD protection will be required.

 
Thanks for the responses.

Yes of course, the overriding need for RCD protection on sockets, forces an RCD to be fitted as they weren't sockets before.

Unless of course this were an office block, and they were going to be used by instructed persons.

I was more thinking of it from the point of view do the cables and their erection method require RCD protection, or would the fact they were existing cables installed to previous version of the regs mean they didn't, and I got blinkered and missed the obvious need for an RCD on sockets.

 
Last edited by a moderator:
1) Additional protection for sockets.

2) RCD protection for buried cables less than 5 feet deep in the wall .

I'd go for the cheap RCD main switch myself ,quick and simple way to cover the rectal orifice, if it trips , lots of other sockets to use .

 
Top