Shaver Socket from a Ring Final

[Marcus Vaughan]

Hi All,

A customer has asked for a shaver socket to be installed in his bathroom.

The only issue is that there is no lighting circuit available (loft conversion above and no access to the eaves).

His idea was to come off a socket in a bedroom on the other side of a stud wall to the proposed location.

I'm assuming its a ring final.

My first thought was - yeah - but I'll have to put a fused spur.

Then I thought - wait a minute - shaver sockets are 230 volts anyway - and have their own inbuilt thermistor to trip at only 200mA.

I can't see any regulation or design problem that enforces the need for the fused spur - so I could just run a 2.5mm or even a 1.5mm to it? Its not a fixed load as such, it can't be overloaded.....

Bad practice?
I am wondering what others would do?

I suggested a mirror light with integrated shaver scocket - which are SELV - now that I would fuse down because the light is a fixed load...

 

[Rpa07]

You could run a flex all the way from the shaver socket and put a fused spur in the bedroom and you’ll have your point of safety - you could make it an RCD fuse spur if the RFC isn’t protected.

 

[Marcus Vaughan]

You could run a flex all the way from the shaver socket and put a fused spur in the bedroom and you’ll have your point of safety - you could make it an RCD fuse spur if the RFC isn’t protected.

Thanks for the reply. Its a standard RCD protected split board.

Routing the cable should be OK - the bedroom socket is literally on the other side of the wall - just need a bit of luck with studs and noggins etc. I think I'm wondering whether I need to fuse it down....

 

[Rpa07]

Find out what breaker it is on then go from there. I understand where you’re coming from though. Interesting question.

 

[Marcus Vaughan]

I took a photo of the consumer unit - 'upstairs sockets' on a B32.
Gotta be a ring!

 

[Strima]

What do the manufacturers say?

 

[Marcus Vaughan]

What do the manufacturers say?

Nothing about fusing down - I've been looking at an MK Logic Plus (have had one in my van for 18months!).

I note that the terminals will take 2 of 2.5mm or even 1 of 4mm - seems a bit keen that for 200mA ?!

 

[Strima]

I'd err on the side of caution and use an FCU fused right down to 3 amp.

 

[Marcus Vaughan]

I'd err on the side of caution and use an FCU fused right down to 3 amp.

Thanks for that - and that's what I have quoted for. I just think, if I found it set up without the fusing down if doing an EICR then it would be a n0-code.

Interesting....

 

[Wilko]

Hi MV - I must admit to having never thought about this, as I've always got supply direct from the light circuit or a 3A fcu.

 

[westward10]

Is the purpose of the thermister to limit the output of the isolating transformer by restricting the primary current although I can see where you are coming from. My issue is the accessory does not comply to BS1363 which according to App 15 which I realise is advisory does not make it suitable for direct connection to a ring final circuit.

 

[Marcus Vaughan]

My issue is the accessory does not comply to BS1363 which according to App 15 which I realise is advisory does not make it suitable for direct connection to a ring final circuit.

That makes sense. I can see it now at the top of Appendix 15 - as you say - references BS1363 only. That’s good enough for me, advisory or otherwise.

3 amp fused spur it is .

I still don’t think I would code it on an EICR though, and come to think of it I have seen the spurred direct of a ring arrangement during an accessory swap for someone - I didn’t bat an eyelid at the time....

Thanks all.

 

[Pete999]

I took a photo of the consumer unit - 'upstairs sockets' on a B32.
Gotta be a ring!

Don't assume anything Marcus! check first Mate.

 

[richy3333]

Agree with Westward (and Pete) as to the approach to take

 

[Shoei]

Hi All,

A customer has asked for a shaver socket to be installed in his bathroom.

The only issue is that there is no lighting circuit available (loft conversion above and no access to the eaves).

His idea was to come off a socket in a bedroom on the other side of a stud wall to the proposed location.

I'm assuming its a ring final.

My first thought was - yeah - but I'll have to put a fused spur.

Then I thought - wait a minute - shaver sockets are 230 volts anyway - and have their own inbuilt thermistor to trip at only 200mA.

I can't see any regulation or design problem that enforces the need for the fused spur - so I could just run a 2.5mm or even a 1.5mm to it? Its not a fixed load as such, it can't be overloaded.....

Bad practice?
I am wondering what others would do?

I suggested a mirror light with integrated shaver scocket - which are SELV - now that I would fuse down because the light is a fixed load...

Interesting question, MK has a pdf of the MIs here, they look a bit dated and generic (isolated/non isolated, red-black wires) but presumably they're still valid. It says this about the mains supply..

5. Isolated shaver supply units should be connected to a mains supply protected by an MCB or fuse of 10 amps maximum rating, such as lighting circuit, or alternatively to a fused connection unit that complies with BS1363: Part 4 supplied from a ring circuit.

So it looks like a fused spur is required to meet the 10A protection spec.

 

[Rpa07]

By an MCB 'or alternatively' an FCU so the MI does give you the assessed choice!

Interesting question, MK has a pdf of the MIs here, they look a bit dated and generic (isolated/non isolated, red-black wires) but presumably they're still valid. It says this about the mains supply..

5. Isolated shaver supply units should be connected to a mains supply protected by an MCB or fuse of 10 amps maximum rating, such as lighting circuit, or alternatively to a fused connection unit that complies with BS1363: Part 4 supplied from a ring circuit.

So it looks like a fused spur is required to meet the 10A protection spec.

But in this case as MV is coming from an RFC then FCU with max 10amp fuse it is.

 

[Shoei]

By an MCB 'or alternatively' an FCU so the MI does give you the assessed choice!

True, I was referring to @Marcus Vaughan s application with a 32A protected ring.

Edit:
That pdf link I posted does look out of date so I had another look at the MK site, this one seems more current, a generic instruction set (Wiring Devices Technical) for a range of MK Logic stuff include the Logic+ shaver socket. It doesn't say anything about supply protection but does mention internal protection for the transformer.

@Marcus Vaughan , does that one on the van still have its MIs? Maybe they improved protection on later units to avoid the need for an FCU.

 

[Marcus Vaughan]

@Marcus Vaughan , does that one on the van still have its MIs? Maybe they improved protection on later units to avoid the need for an FCU.[/QUOTE]

I just had a look, pulled it out of the box, but no instructions with it?

 

[DefyG]

If you had discovered that doing an EICR what would you have thought? ……..
Its a spur off a ring circuit so therefore ok? The safety isolating transformer cannot supply more than its design current!

Ive come across this before when doing a bathroom refurb some years back and initial thoughts were that it is wrong but couldn't find anything in the regs to support that.

 

[Marcus Vaughan]

If you had discovered that doing an EICR what would you have thought? ……..
Its a spur off a ring circuit so therefore ok? The safety isolating transformer cannot supply more than its design current!

Good question. Earlier I said it would be a no-code but now I'm leaning towards a C3 - because of the replies above mentioning appendix 15 and those manufacturing instructions.

Ive come across this before when doing a bathroom refurb some years back and initial thoughts were that it is wrong but couldn't find anything in the regs to support that.

I think they'll be a lot of examples of it - but I cannot see any real risk with the set-up.

Does not mean I'm going to do it though - I am going to fuse it down. To ambiguous an issue not to.