Lighting Ring Extended to Sockets

[tnarg999]

I've got this rental property (1st & last..) approx 10 years old. Tenants are moving out. Did a pre-move out inspection and most of the upstairs ceiling light fittings look to have been overheating (brown to dark brown around the cream bayonet holders - half sphere type glass light fittings)

Tenants said the bulbs blew a lot and replaced most with CFL efficient bulbs (11 Watt I think). So I replace the damaged light fittings with surface mount and pendants where necessary. Plugged in the Dyson to tidy up and the MCB flipped on the upstairs lighting circuit.. What have I done!!? This is pre 17th so no RCD/RCBO on the lighting. Plugged in the socket tester where the Dyson had been, 2 green lights so appeared to be wired correctly - flipped the MCB to off on the lighting circuit and the socket stops working.
Take the face plate off the socket, 1 pair of 2.5mm grey T&E so more recent than the house. Trace the wire through the wall up some conduit where it disappears into the loft presumably extended and terminating into the lighting socket. (need to check this tonight)

It appears the previous owner wanted power on the other side of the room for a TV, and the nearest electric without destroying the chipboard floor was the loft and hence the lighting circuit. Could this have caused overheating on the light fittings when a TV/HIFI/Dyson were plugged into the lighting circuit?

Guess I've got some work to do - moral of story - never assume anything.

 

[kevindgas]

Could this have caused overheating on the light fittings when a TV/HIFI/Dyson were plugged into the lighting circuit?

Guess I've got some work to do - moral of story - never assume anything.

yes - lighting circuit should be 5or 6amp on 1.0 or 1.5 mm cable
sockets on the other hand should be 20 - 32Amp on 1.5 or 2.5 mm
the two must not be mixed.

i would suggest a full inspection as overloading like this will probably have brought other faults like cable insulation breakdown

 

[stem]

It wouldn't have caused any damage as the MCB would trip if too much current was drawn as you found out. That's what it's there for to protect the wiring from an overload.

The bayonet fittings have probably just deterioated from the heat of the bulbs, it's very common, especially as the heat becomes trapped at the top of the globes.

 

[holmslaw]

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[rebuke]

Assuming they didn't change the breaker (which given it tripped with your dyson it sounds like they didn't), then no, it shouldn't have caused your light fittings to overheat, since they should be designed to cope with the amount of current the circuit was rated to.

You mention they are looking burnt around the bayonet holders - this is quite common, especially if 100W bulbs are used (a lot of holders are only rated to 60W, so a 100W bulb causes them to get too hot).

Given that the previous owner put a socket on the lighting circuit, I'd be inclined to get a PIR done (periodic inspection report) by a qualified spark, which will hopefully spot any other 'dodgy' bits of wiring in the property - especially important if you rent it out, since you have a duty as a landlord to ensure the property is electrically safe...

 

[tnarg999]

You mention they are looking burnt around the bayonet holders - this is quite common, especially if 100W bulbs are used (a lot of holders are only rated to 60W, so a 100W bulb causes them to get too hot)

Could this also have caused the bulbs to repeatedly blow?

This looks to be about the only non-original wiring done in the property (except for the electric shower which a qualified NICEIC did for me), but I take your point about a PIR and I should consider it. After all, it gives peace of mind and for a small 2 bed semi isn't going to cost mega $$s.

 

[kevindgas]

sockets on the other hand should be 20 - 32Amp on 1.5 or 2.5 mm

That is incorrect, 20A socket circuits should be 2.5mm, and 32A should 2.5mm if a ring and 4mm if a radial.

if you wish to be pedantic then at least check all the facts as ring 30/32 Amp can be 2.5mm and a spur off if fitted through a FCU can be 1.5
READ P362 BS7671:2008 For clarification

a radial on 20 amp 2.5mm
but a radial on 30/32 amp consists of 4mm as you correctly pointed out
but an unfused spur (which is from what is written the OP has) to the socket can be 2.5mm as i said. in addition if fitted with a FCU the spur could be on 1.5mm
READ P363 BS7671:2008 For clarification

as for the original question I would still have a full check done as the circuit is wrong and has been subject to overload.

 

[ColJack]

given that this is a DIY forum, he was trying to clarify what you said kevin...

you said you can have a 20A radial in 1.5 cable.. and you can't...

you can have a socket fed from a 13A fused spur, but that's not then a 20A radial is it?

he's just trying to stop fred blogs from taking your post at face value and wiring a socket radial in 1.5 from a 20A breaker..

 

[kevindgas]

given that this is a DIY forum, he was trying to clarify what you said kevin...

you said you can have a 20A radial in 1.5 cable.. and you can't...

you can have a socket fed from a 13A fused spur, but that's not then a 20A radial is it?

he's just trying to stop fred blogs from taking your post at face value and wiring a socket radial in 1.5 from a 20A breaker..

agree with advising when something is misleading. But when pointing out something it is best to put all the detail not just the bit you wish to pick holes in!

 

[kevindgas]

you said you can have a 20A radial in 1.5 cable.. and you can't...

Actually I didn't

 

[holmslaw]

..

 

[kevindgas]

sockets on the other hand should be 20 - 32Amp on 1.5 or 2.5 mm

Thats what you said and it is wrong - shame you can't admit it - but who cares, everyone else can see what you said, and they know its wrong.

Coljack is quite right as to my intentions.

Bit touchy aint yer.

in this quote does it say 20amp on 1.5mm NO IT DOES NOT!!!

 

[kevindgas]

Take the face plate off the socket, 1 pair of 2.5mm grey T&E so more recent than the house. Trace the wire through the wall up some conduit where it disappears into the loft presumably extended and terminating into the lighting socket. (need to check this tonight)

i think you will also find this quote in OP's first post in which he says "1 pair of 2.5mm" end of!!

 

[ColJack]

it's got sod all to do with what the OP said..

you quite clearly state that sockets should be 20 to 32A, and on 1.5 OR 2.5 cable...

sockets fed from a breaker of rating 20 to 32A absolutly should NOT be fed in 1.5 cable, unless it's being fed from the load side of a fused spur, thus limiting the maximum current the cable has to carry, to 13A..

 

[holmslaw]

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