A couple of questions on domestic electrics

[eltax91]

Hi all, I have a couple of brief questions, hopefully they are simple enough, would love to get a few weighted opinions.

Firstly, I need to fit an additional socket in the house. I'm not worried about the wiring, I have installed a fresh (working) ring main in the garage and it all worked! Anyway, I have 2 options to spur this new socket from. Either the ring main in the garage, which will required several holes in 3 walls to route the cable, this would mean it would be a single spur from one of the sockets on the ring main. Possible but a pain in the arse. Alternatively, right on the other side of the wall where I want the new socket is a socket. It has 1 set of cables in the back, so i think it's a spur? If so, how naughty is it to "spur from a spur"? The spur runs a laptop power supply and occasionally the ipod dock. The new socket will run a wireless router and cordless phone. So, any thoughts?

Secondly, in the loft I need to rig up a light. There is no lighting electrics nearby. Can I just use some "lighting cable" I have left over, wire it into a 3pin plug and stick a spare ceiling rose on the other end? If so, what size fuse do I need?

Cheers in advance for any advice.

[DrDeAtH]

get an electrician to do it properly. i take it you were able to test your new ring circuit and fill out the appropriate test form.

[Flintstone]

DrDeAtH said:

get an electrician to do it properly. i take it you were able to test your new ring circuit and fill out the appropriate test form.

Probably not but I assume nobody died either. I've not yet killed anybody with the lights in my loft or the security lights outside my house.

Must try harder.

[Mr POD]

eltax91 said:

Hi all, I have a couple of brief questions, hopefully they are simple enough, would love to get a few weighted opinions.

Firstly, I need to fit an additional socket in the house. I'm not worried about the wiring, I have installed a fresh (working) ring main in the garage and it all worked! Anyway, I have 2 options to spur this new socket from. Either the ring main in the garage, which will required several holes in 3 walls to route the cable, this would mean it would be a single spur from one of the sockets on the ring main. Possible but a pain in the arse. Alternatively, right on the other side of the wall where I want the new socket is a socket. It has 1 set of cables in the back, so i think it's a spur? If so, how naughty is it to "spur from a spur"? The spur runs a laptop power supply and occasionally the ipod dock. The new socket will run a wireless router and cordless phone. So, any thoughts?

Secondly, in the loft I need to rig up a light. There is no lighting electrics nearby. Can I just use some "lighting cable" I have left over, wire it into a 3pin plug and stick a spare ceiling rose on the other end? If so, what size fuse do I need?

Cheers in advance for any advice.

One question for you. If you plugged a 4 way extention lead into this spur, and ran a dish washer, electric heater, washing machine and kettle all at full blast, would there be a problem ?

The lighting one is easy. Do you have any table lamps ? What size fuse does that have ?

[Deva Link]

Mr POD said:

One question for you. If you plugged a 4 way extention lead into this spur, and ran a dish washer, electric heater, washing machine and kettle all at full blast, would there be a problem ?

Not really - the 13A fuse in the extension lead plug would blow.

[Mr POD]

Deva Link said:

Mr POD said:

One question for you. If you plugged a 4 way extention lead into this spur, and ran a dish washer, electric heater, washing machine and kettle all at full blast, would there be a problem ?

Not really - the 13A fuse in the extension lead plug would blow.

So is that the answer then ? Put a breaker between the existing spur and the new spur ?

Electricians hate people like me.

[Deva Link]

When a "proper" electrician wired our extention with a double socket either side he just ran them from the nearest socket on each side of the existing room. One of those was already a spur.

I asked him what would happen if someone plugged two 13A heaters in and he cheerfully said the cable would melt.

[ColinM50]

Don't you just love all these doom sayers with their "what if someone plugged the Hadron Collider in to your wall socket" rubbish? You know what sort of load it's going to have on it and if as you say it's just a charger and Ipod dock, then the way you suggested i.e. off an existing spur will be fine. Put a 3 or 5 amp fuse on it.

It's not rocket science and very little chance of anything going wrong and if it did your MCB would trip before anything serious happened.

[Raverbaby]

ColinM50 said:

It's not rocket science and very little chance of anything going wrong and if it did your MCB would trip before anything serious happened.

A standard ring main is normally protected a 32A MCB/RCD.
Under the best conditions, a "spurred" 2.5 T&E cable can only carry 27A, so that could overheat.
A 32A MCB will not trip instantly at 32A, it could easily carry 35A so again there is potential for overheating.
These sockets always start off as a point "just for a charger" but quickly grow arms & legs.
If altering the ring main isn't possible and you want to spur off a spur, you could then make your first point a 13A FCU (spur) and then run as many sockets as you like from the load side.

[Deva Link]

Raverbaby said:

A standard ring main is normally protected a 32A MCB/RCD.
Under the best conditions, a "spurred" 2.5 T&E cable can only carry 27A, so that could overheat.
A 32A MCB will not trip instantly at 32A, it could easily carry 35A so again there is potential for overheating.
These sockets always start off as a point "just for a charger" but quickly grow arms & legs.
If altering the ring main isn't possible and you want to spur off a spur, you could then make your first point a 13A FCU (spur) and then run as many sockets as you like from the load side.

I think it's quite bizzare (considering how anal some of the regs are) that it's perfectly legitimate to spur a double socket off a ring main without separately fusing it - ie you can just wire it directly from the back of an existing socket on the ring.

[stolt]

i did somethign similar recently and spurred a double socket from spurred socket, like you i knew that what it was for and nothing else, but covered myself as other have said by putting a fused connection switch before the sockets.

I appreciate there are rules and regs there to protect everyone and I agree I dont think i would liek to move into a house that has had DIY electrics done, but at the same time i've had some poor tradesman round that have done shoddy work and supplied the necessary part p certs etc.

[TOPTON]

DrDeAtH said:

get an electrician to do it properly.

Got an electrician to do some wiring on a house a while back. Innitial talk from him was full of safety reasons for doing things and part p section 5 sub cat 2-3 para 7 etc bullst.

He wired from a ceiling rose to a wall , about 1.5m away and up into bedroom, cut a hole either side of the joists and wrapped the wire under and back up. The wire was clipped to the plasterboard side of the joist, so it would effectivly be 3mm under the plaster finish in four places.

When I suggested its lack of safetyness, ie a drawing pin holding a ballon up would pierce the wire, he said and I quote "that's fine, no one will die because there are cirtuit breakers fitted."

He ran a socket spur from an upstairs room down a wall about 1m, then ran it off at 45deg to socket height near the floor.

But hey, he was qualified eh! Needless to say, he didn't stay on the job any longer

[Ganglandboss]

TOPTON said:

Got an electrician to do some wiring on a house a while back. Innitial talk from him was full of safety reasons for doing things and part p section 5 sub cat 2-3 para 7 etc bullst.

He wired from a ceiling rose to a wall , about 1.5m away and up into bedroom, cut a hole either side of the joists and wrapped the wire under and back up. The wire was clipped to the plasterboard side of the joist, so it would effectivly be 3mm under the plaster finish in four places.

When I suggested its lack of safetyness, ie a drawing pin holding a ballon up would pierce the wire, he said and I quote "that's fine, no one will die because there are cirtuit breakers fitted."

He ran a socket spur from an upstairs room down a wall about 1m, then ran it off at 45deg to socket height near the floor.

But hey, he was qualified eh! Needless to say, he didn't stay on the job any longer

Qualified? - Maybe
Installed to BS 7671? - No
An idiot? - Yes

[jeebus]

TOPTON said:

Got an electrician to do some wiring on a house a while back. Innitial talk from him was full of safety reasons for doing things and part p section 5 sub cat 2-3 para 7 etc bullst.

He wired from a ceiling rose to a wall , about 1.5m away and up into bedroom, cut a hole either side of the joists and wrapped the wire under and back up. The wire was clipped to the plasterboard side of the joist, so it would effectivly be 3mm under the plaster finish in four places.

When I suggested its lack of safetyness, ie a drawing pin holding a ballon up would pierce the wire, he said and I quote "that's fine, no one will die because there are cirtuit breakers fitted."

He ran a socket spur from an upstairs room down a wall about 1m, then ran it off at 45deg to socket height near the floor.

But hey, he was qualified eh! Needless to say, he didn't stay on the job any longer

This is the problem now with part P, all it has done is allowed anybody to do the three day course and as long as you buy a meter and pay your £500 membership fee you can start calling yourself an electrician and sign your own jobs off. When you hear these horror stories about shoddy work I would say that in 99% of the Cases you have not employed the services of a proper time served spark.

[DrDeAtH]

+1 Jeebus

These '5 day wonders' are destroying the trade, they are not properly qualified, and DO NOT in general have a PROPER understanding of what they are doing and best working practices, but hey 'its only a couple of wires'.....

Part P is a bit of a farce, but that is another discussion...... its just down to poor regulation of the industry.





the RCD will catch it all anyway.... really?

[eltax91]

Well. I wired in the spur socket tonight. Contrary to the doom merchants on here I am still alive!

For whomever it was who asked if I had my DIY ring mains in the garage checked and tested, I wired them up myself, then paid a local spark to wire them to the consumer unit and check my wiring. I had to do this to get council sign off under building regs.

So, my second question, is it ok to wire standard lighting 'grey' cable into a 3 pin plug and a ceiling rose? Also, what size fuse is required. Come in guys, instead of disparaging comments, help me to get it right and not guess.

[Deva Link]

eltax91 said:

So, my second question, is it ok to wire standard lighting 'grey' cable into a 3 pin plug and a ceiling rose? Also, what size fuse is required. Come in guys, instead of disparaging comments, help me to get it right and not guess.

Where is the socket that you intend to plug into - is it in the loft, and, if so, is it within easy reach of the loft hatch?

[Raverbaby]

A 3A or 5A fuse will be fine.
Its a bit rough sticking it on a bit of twin & earth, flex is preferable, but aslong as your connections are sound then it shouldnt be a problem.
Remember to earth sleeve the bare copper earth wire.

[Deva Link]

I wouldn't put a ceiling rose (with a flex dangling) in a loft unless you've got a very high roof. Use a batten lamp holder or some other kind of fixed light unit like a bulkhead lamp, or even a strip light.

If the socket is up there, then use a switched fused spur and hard wire the cable into the back of the socket and fix all the cabling in place. The grey T&E cable isn't designed to be flexed, like flex is!

[PoleDriver]

Yes, it is possible to run a spur off a spur, make it work and not kill yourself.
Yes, it is quite easy for someone with a bit of common sense to follow the regs and connect the system properly.
No, wiring isn't rocket science and the basic theory is very simple to follow.
Yes, many of the new 'rules' (especially part 'P') are just plain stupid!

But, how would you feel if your simple extension to power a couple of IT gizmos gets overloaded by some future purchaser of your house who decides to load it up to 13+amps and starts a fire, killing their whole family??

In the main (pun intended) the majority of the regs are there for very good reasons and short cuts should not be taken!!