Maximum size MCB on a 16A socket outlet

[JVMElectrical]

Hi guys this is my first post asking a question so here goes!

I'm currently having a debate with my boss who is adement that you can only have a 16A MCB on a 16A socket outlet. I'm sure I've seen somewhere in the regs or OSG that the maximum size MCB is a 20A on a 16A socket (Don't ask me why doesn't quite make sense) 7

I haven't got Guidance note 1 to hand but have found it is in there just wondering whether anyone knows where in the OSG or the Regs I could find it!

Would be a real help Thanks Jamie Morris

 

[Mr Mark Sparks]

Don't know with out looking but will stick my neck out and say 16a max

apology ready if wrong

 

[oldtimer]

So what size mcb for a 13amp single socket on its own circuit

 

[ian.settle1]

So what size mcb for a 13amp single socket on its own circuit

OOOOOOOOH didin't know they made a 13A MCB

 

[Mr Mark Sparks]

Does the fuse in the plug not provide the 13a protection in this case

 

[Mr Mark Sparks]

OOOOOOOOH didin't know they made a 13A MCB

ABB S201M-C13 - Miniature Circuit Breakers MCBs - Modular DIN Rail Products

This is how sad I am I've found one.

 

[markc123]

minimum of 16A for a 16amp socket. Says in the regs, don't have the regs to hand but its in section 708 somewhere - only 3/4pages long, won't take you long to find.

 

[markc123]

Reading the other comments on this thread, i may be mistaken - seen as though you lot are on about 13a sockets now lol. But im pretty sure the OP meant 16A commando sockets.

 

[JD6400]

Reading the other comments on this thread, i may be mistaken - seen as though you lot are on about 13a sockets now lol. But im pretty sure the OP meant 16A commando sockets.

I think it was for a commando as well .
I have not looked it up but i would say that it would be 16A , and i have always installed as such .

 

[markc123]

Aye same, It's def in the regs under section 708 just can't remember the exact reg + cba to go to my van and get the BGB lol.

 

[Engineer54]

You can have a 6A, 10A, 16A MCB supplying a single 16A socket, depends on the wiring size used and what the socket is being used to supply!! The 16A designation for the socket, is the limitation of the CC ability of the plug & socket itself. Doesn't make much sense to protect a single 16A socket with a 20A MCB though!!
Although you can say the 20A MCB is still protecting the cable, if were talking about it being wired in 2.5mm cable!!

 

[scotsparky]

Engineer i have had a few sherbets and i agree! The MCB size relates to the cable size and desigh current not the rating of the outlet!

 

[Engineer54]

Exactly, It's perfectly permissible to have more than one 16A socket outlet on a circuit with a 20A MCB or other protective device, if the cable size and design current permits!! It's just pretty pointless, to have a 20A MCB on a single 16A socket circuit, be it being allowed or otherwise by BS7871.

 

[Brightspark2]

by BS7871.

Oh really...the British standard for pneumatic conveying...lol

 

[Rockingit]

A standard 13A single socket is protected by a 32A CPD if it's sat on a ring, have a think about that.

 

[telectrix]

all depends on whether it's just 1 socket on the circuit or several. could be 6/7 16A sockets on a 10mm cable with a 50A OCPD

 

[Mr Mark Sparks]

A standard 13A single socket is protected by a 32A CPD if it's sat on a ring, have a think about that.

As I said earlier the plug top fuse provides the protection

 

[Mr Mark Sparks]

all depends on whether it's just 1 socket on the circuit or several. could be 6/7 16A sockets on a 10mm cable with a 50A OCPD

So 45a mcb 10mm cable to 1 socket would be "wrong" but 3 would be " ok "
I can't see how that's ok especially if you can't control what's going to be plugged in.

 

[telectrix]

each socket is limited to 16A as whatever is plugged into a socket will have been designed for <16A , otherwise it would not have a 16A plug on it. the circuit OCPD is to protect the circuit cable.

 

[Mr Mark Sparks]

:rolleyes2:Just to be argumentative..
a garage owner buys a 2 nd hand welder with no plug on and he or someone else sees the spare 16a socket (protected by 45 a mcb) and puts 16a plug on, turns out the welder is 32a..
just making a point really