RCD

[Newb1]

Hi chaps, sorry if this is daft, but new.

The new 18th says circuits supplying sockets in domestic dwelling up to 32a need rcd protection. 

However, if you come to a house thst has an old board with 3036 fuses say, and they want an additional socket, but don't want a board upgrade, then you could stick an RCD socket in. 

But how does this comply as then I assume only the socket and appliance is protected and not the actual new circuit. 

Thanks in advance. 

 

[Sidewinder]

Welcome to the forum.

BS1363 socket outlet and fused connection RCD devices to BS7288, (/EN51643) are no longer listed in BS7671:2018, it is not yet clear if this is yet another mistake or, if it is a deliberate removal of these devices.

Now, what you say about the connected appliance only, being protected is correct.

So, if you are to modify the system, then you need to verify earthing and bonding is adequate, then ensure that your installation method/the modified circuit complies with the current requirements of BS7671.

Remember, you can add an RCD n a separate enclosure external to the board to protect the socket circuit, remove the ring from the MCB, fit to the outgoing side of the external RCD, wire between the 3036 & the RCD such that the wiring does not require RCD protection, and is adequate for the protective device.

It’s a bit like a lollipop circuit.

Not a perfect option, but, safer than no RCD, and safer than a single RCD socket, as you would be adding RCD protection to the whole circuit.

Just be sure the circuit is sound before modifying it, and check/warn about old appliances which may trip the RCD.

 

[Murdoch]

Thing to remember with lots of old BS 3036 boards is that the earthing and bonding are often inadequate or missing ...

as for RCD sockets, I think the IET had made an error .....which isn’t unusual

 

[Sidewinder]

...

as for RCD sockets, I think the IET had made an error .....which isn’t unusual

Quite Murdoch, but, they are being VERY slow in clarifying the situation, which is really annoying.

 

[Murdoch]

Quite Murdoch, but, they are being VERY slow in clarifying the situation, which is really annoying.

Im assuming it’s a mistake, seeing as these parts are still readily available

got my assessment coming up .... I may ask about this !

 

[Sidewinder]

Im assuming it’s a mistake, seeing as these parts are still readily available

got my assessment coming up .... I may ask about this !

Your assessor probably won’t know he official answer, the head technical “guru” for Stroma sits on JPEL/D and he’s not sure!

I’ve asked the chair of that panel, and a couple of other panel members & chairs and a few who sit direct on JPEL and nobody could give me a straight answer!

 

[Murdoch]

Your assessor probably won’t know he official answer, the head technical “guru” for Stroma sits on JPEL/D and he’s not sure!

I’ve asked the chair of that panel, and a couple of other panel members & chairs and a few who sit direct on JPEL and nobody could give me a straight answer!

God help us ..... they shouldn’t be making decisions on our regs

cant we oust the lot of them and start again?

 

[Murdoch]

The IET should learn from golf !

https://www.golf-monthly.co.uk/news/new-golf-rules-2019-152161

 

[Blue Duck]

Welcome to the forum.

BS1363 socket outlet and fused connection RCD devices to BS7288, (/EN51643) are no longer listed in BS7671:2018, it is not yet clear if this is yet another mistake or, if it is a deliberate removal of these devices.

There is some guidance floating about from the NIC man saying that they can be used but listed as a deviation.

Makes no sense to exclude them in some situations, but they do not provide circuit protection just outlet protection.

 

[Murdoch]

There is some guidance floating about from the NIC man saying that they can be used but listed as a deviation.

Makes no sense to exclude them in some situations, but they do not provide circuit protection just outlet protection.

How can it be a deviation ? 

 

[Doc Hudson]

Hi chaps, sorry if this is daft, but new.

The new 18th says circuits supplying sockets in domestic dwelling up to 32a need rcd protection. 

However, if you come to a house thst has an old board with 3036 fuses say, and they want an additional socket, but don't want a board upgrade, then you could stick an RCD socket in. 

But how does this comply as then I assume only the socket and appliance is protected and not the actual new circuit. 

Thanks in advance. 

The requirements for RCD protections on sockets (and the cables buried in the walls) is not a new requirement, been around since 2008 IIRC. So just give the customer a price for doing the job correctly, to make it comply with the regulations that are now over 10years old. ( possibly a full board replacement or additional small unit just for your amended circuit?  ).  However in these situations you will typically find other aspects of the installation also no longer comply with BS7671. Probably earthing & bonding out of date. Very likely no previous inspection & test over the last 10 years. Maybe incorrect fuse ratings as ring no longer intact. Or deteriorated or damaged cables that you can't extend anyway. Possibly insufficient circuits to meet the minimise inconvenience aspects.  Personally I would be recommending a full inspection & test first, unless you have copies of up-to-date condition report, before doing any work on installations with old CU's like your example.  As 132.16 requires you to check the rating & condition of existing equipment beforehand, are you confident that the existing board is adequate anyway? (RCD protection is only a small part of your problem in my opinion)

The bottom line is, if you do something and it goes pear-shaped later because you have chosen to skip some of the industry standard guidance which is there to protect people property & livestock, you may need a very good defence case to explain your actions. If you consider something is potentailly dangerous and/or non compliant with BS7671, how can you put you name on an electrical certificate saying to the best of your knowledge it has been designed installed and tested in accordance with BS7671?  Unless of course you adopt the method too often done: Do the job, ignore testing & regs, take the cash, leave no paperwork, ride off into the sunset on your horse with the dust floating around your cowboy hat.

Doc H.

 

[Evans Electric]

There is some guidance floating about from the NIC man saying that they can be used but listed as a deviation.

Makes no sense to exclude them in some situations, but they do not provide circuit protection just outlet protection.

Complications arose when we were obliged to give RCD protection to cables buried in walls  but I assume a surface SWA  cable feeding an RCD socket  has their royal blesssing .   Or any of the light grade cables with an earthed sheath.  

Note to Newb1   with the opening post ............  don't worry about what you may think are  daft questions  ...your question wasn't at all  daft  ..feel free to ask away . 

The only time members get a bit "frosty"  is with the  "Know it Alls"  , the  " Big 'eds "  and the   ones who should be banned from even opening a Sparkie's toolbox .

Welcome to the Forum .   

 

[Newb1]

Cheers chaps, I'm still an apprentice, third yr, I'm pretty compitant at testing and what not, it's just as I don't do a lot of job organising myself, I'm still a Bit unsure if the total regs, the job itself, is my nan, she just wants a Extra socket in her garage, and I was going to do it and use some SY flex surface mounted, clipped direct, as I need that cable to finish off my port folio, because I dont really use it so there is no opportunity I have to do it like this.

Her house has not been touched since it was built, so everything complies to the edition it was built in (I would assume), I have not checked the characteristics of the supply yet, so don't know if it's a TN-S where with 16mm tails and 60a fuse. If so the bonding would be ok at 6mm, other wise I'll upgrade them. Obviously I'll do all the correct test and inspection, but I was not sure about the rcd protection, and although I could mount a housed rcd next to the board, I was wandering, as it's clipped direct, I'll gland gland it off so the sheath is earthed as well as a 3rd core and the run is only 2 meters I was wandering if an RCD socket would suffice, as the regs were not clear and there is no mention of SYflex being acceptable to omitte Rcd like with SWA. 

 

[Murdoch]

SY flex ...... are you sure?

 

[Sidney]

I asked the NIC tech helpline a couple of months ago and they stated it was perfectly acceptable to use RCD socket-outlets if the installation method allowed.

And I second the SY question...

 

[Newb1]

Yeah, i know its not the best cable and stuff, but in my apprenticeship, I have to show examples of using 

Thermosetting insulated cable 

Pvc flat profile cable 

Singles 

MICC

SWA 

Amoured braided flex (my thinking SY)

Date 

FP200

 

[Murdoch]

Sy isn’t suitable for fixed installations imho

that said see it being used more these days .... quite why is beyond me

 

[Newb1]

Yeah we just carried out a massive EICR on a factory, loads of SY flex, ranging from 1mm to 185 size... it failed 

 

[Doc Hudson]

"7.9 Installation and use of non-standard cables" page 90 of OSG discourages it use. That refernces 133.1.1, 511.1 & 511.2

Doc H.

 

[Blue Duck]

How can it be a deviation ? 

They aren't listed therefore it must be a deviation? 

I guess that's how it works.

Golf is for W's   :lol: