socket safe

[curt83]

Help need please. replacing socket fronts in hallway and single one has 3 live,3 neutral,3 earth going in to it is this correct and safe? 2 of the cables come from under floor board and 1 looks like its supplying my loft, any info would be great cheers curt

 

[securespark]

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.

 

[sparkwright]

It sounds like it could be ok. Quite normal to spur off a socket with a third cable.

Some questions though.

Do all the cables look the same size? They should be.

What exactly in the loft does this cable supply? One socket or a 'fused spur unit' would generally be ok.

 

[curt83]

All wire looks same size. Theres 3 single sockets in my loft?

 

[sparkwright]

What size fuse or MCB at the consumer unit or fuse box protects this circuit?

 

[curt83]

it says b32 on the mcb

 

[sparkwright]

I ASSUME the cable is 2.5 mm2 and wired in a ring.

We don't know for sure if the 'spur' cable at the socket is feeding the loft at this stage, do we?

Can you trace the wiring from this socket to the loft, and describe the layout of the wiring ie how many cables at each loft socket.

Also look out for any 'fused spur units' which may form part of the circuit.

Photos and diagrams most helpful.

 

[elrobbo82]

Do all the cables look the same size? They should be.

do they have to be if supplying a single 13A socket or could you use 1.5mm as the single 13A socket would be limited to a max 13A?

as stated more investigation needed.

 

[RF Lighting]

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

(Clue: the answer is no)

 

[ban-all-sheds]

I ASSUME the cable is 2.5 mm2 and wired in a ring.

We don't know for sure if the 'spur' cable at the socket is feeding the loft at this stage, do we?

Nor, regarding your assumption, do we know if the circuit is a ring or if the cable is 2.5mm²...

If your assumption is correct, and if there's a spur into the loft, then not only are there too many sockets on it, a 2.5mm² unfused spur cable is unlikely to comply with 433.2.2(ii).

As you say - much more information needed.

 

[elrobbo82]

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

(Clue: the answer is no)

1.5mm would though.

did not state reference method or cable type. just asked the question.

 

[ericmark]

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

(Clue: the answer is no)

1.5mm would though.

did not state reference method or cable type. just asked the question.

My book says 1.5mm Ali-tube cable clipped direct 24A. The only cable able to take more current would be mineral insulated and that's not a DIY job.

Even mineral insulated only rated at 28A ref method C and we would not expect it to be in free air or on a perforated cable tray when used in a house and even that's 31A not 32A.

 

[ericmark]

If the first socket was replaced with a fused connection unit then likely it could be made to comply. However to assume is dangerous and no one can remotely give you answers with the information we have.

 

[elrobbo82]

My book says 1.5mm Ali-tube cable clipped direct 24A. The only cable able to take more current would be mineral insulated and that's not a DIY job.

Even mineral insulated only rated at 28A ref method C and we would not expect it to be in free air or on a perforated cable tray when used in a house and even that's 31A not 32A.

the 1.5mm cable would in the instance i stated be limited to a max of 13A due to a 13A single socket being attached at the end.

also with regards to being able to use 1mm cpc on a 32A b type mcb you would have to carry out the adiabatic equation for the fault current. so it depends on the measured ZS.

not saying that i would install this but wether it complies or not is a different story.

 

[sparkwright]

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