socket safe

[elrobbo82]

No self respecting electrician would choose to feed a socket from a ring circuit in 1.5 mm cable.

as stated i would not install using this method. but if you came across this scenario on a PIR what code would you give this if any with regards to BS7671. as i said wether it complies or not is a different story. we are in a world where bad practice is rife yet complying to the regs does not eliminate it entirely does it.

 

[RMS]

Is a 1.0mm² CPC suitable for use on a B32 device?

(Clue: the answer is no)

Please elaborate?

 

[RF Lighting]

Do the adiabatic equation and see what answer you come up with.

 

[securespark]

Is a 1.0mm² CPC suitable for use on a B32 device?

(Clue: the answer is no)

But an RF circuit with 1.0mm2 CPC is acceptable, no?

 

[JohnW2]

Do the adiabatic equation and see what answer you come up with.

The problem with doing an adiabatic calculation on the basis of the data in the BRB/BGB is that their graphs of disconnection times do not go below 0.1 secs. If one works with a fault current of 660A (Zs ~0.35Ω at 230V) and a disconnection time of 0.1 secs, the minimum copper CPC ('k' = 115)appears to be about 1.8 mm² for a B32 MCB.

However, most manufactirers indicate that the disconnection time is actually less than 0.01 secs - at 0.01 secs, the mimimum CPC would be about 0.57mm² , and if <0.01 secs, smaller even than that (although, if it actually applies to CPCs {a CPC is a 'conductor, isn't it?!}, Table 52.3 imposes a minimum of 1mm².

Kind Regards, John.

 

[Beelzebub666]

Blimey, he just asked if it's a problem to find three cables in a socket. He's only replacing the socket outlet.

It's common to find a spur off a ring, if you're just replacing the fronts you aren't expected to worry about all the latest wiring regulations. No one can tell you it's correct and safe without looking at it, but seeing three cables instead of two doesn't mean you have a reason to think it isn't.

 

[JohnW2]

Blimey, he just asked if it's a problem to find three cables in a socket. He's only replacing the socket outlet. It's common to find a spur off a ring, if you're just replacing the fronts you aren't expected to worry about all the latest wiring regulations. No one can tell you it's correct and safe without looking at it, but seeing three cables instead of two doesn't mean you have a reason to think it isn't.

Dead right! Tangential discussions following the answering of an OP's question are common enough, and often quite interesting - but, having stumbled across this thread only late, I hadn't noticed that no-one had really answered the OP before the thread got distracted!

Kind Regards, John.

 

[elrobbo82]

Dead right! Tangential discussions following the answering of an OP's question are common enough, and often quite interesting - but, having stumbled across this thread only late, I hadn't noticed that no-one had really answered the OP before the thread got distracted!

Kind Regards, John.

op was answered with the first two replies.

 

[ban-all-sheds]

Seems OK. It could be one in, one out (like a ring final circuit), plus a spur to the loft.

But without testing the circuit, you can't be sure.

It sounds like it could be ok. Quite normal to spur off a socket with a third cable ... What exactly in the loft does this cable supply? One socket or a 'fused spur unit' would generally be ok.

But we now know that

Theres 3 single sockets in my loft?

So yes, it has flown off at various tangents, and we need to get back to this:

Curt - you need to find out if that socket is supplying those 3 sockets as an unfused spur.

If it is you need to put an FCU in next to the socket, with a 13A fuse, and connect the spur to that.

 

[JohnW2]

op was answered with the first two replies.

Only partially - those first two replies were both such as to put/leave doubts in the OP's mind.

Kind Regards, John.