Recent Electircal Work Questions

[vards01]

Hi all,

I have just had some electric works done and wanted to check a few things were all above board.

Can you extend a cooker circuit by joining the cable (crimping), old 60's style metal switch backbox left in place new cable joined to existing inside this and filled? Two points here is it OK to leave the backbox in the wall and join the cable in this manner, when carrying high loads?

Is it a requirement to use conduit in a chase, or is it permissible to cable clip to the wall and plaster straight in. (basically means wrecking the wall if ever the cable need to be replaced.

Similar to point 1...but with a standard socket moving it down......joining (crimping) cable then filling in leaving the original back box in place.....plastic one this time.

Having loose cable around the back of kitchen units, should point out when the kitchen is installed you cannot access the cable as it is behind the units, the purpose of this is to allow surface mount socket to be affixed inside cabinet.

Really just wanted some confirmation this is standard practice, as I would have done it differently myself. But not being an electrician this isn't an option these days.

 

[EFLImpudence]

Can you extend a cooker circuit by joining the cable (crimping), old 60's style metal switch backbox left in place new cable joined to existing inside this and filled? Two points here is it OK to leave the backbox in the wall and join the cable in this manner, when carrying high loads?

It is if done correctly.

Is it a requirement to use conduit in a chase, or is it permissible to cable clip to the wall and plaster straight in. (basically means wrecking the wall if ever the cable need to be replaced.

That's fine.
Why would you want to replace?

Similar to point 1...but with a standard socket moving it down......joining (crimping) cable then filling in leaving the original back box in place.....plastic one this time.

It is alright if the new cable run is straight on from the old.

Having loose cable around the back of kitchen units, should point out when the kitchen is installed you cannot access the cable as it is behind the units, the purpose of this is to allow surface mount socket to be affixed inside cabinet.

Cables acceptable but would be better clipped if possible.

Sockets technically acceptable if units are fit for the purpose but naff.
Why do/did you want sockets inside the units.
Mounted on the wall at the back with a very neat cut-out is much better.

Really just wanted some confirmation this is standard practice, as I would have done it differently myself. But not being an electrician this isn't an option these days.

No, but you can ask for what you want and if not against any regulations then it should be done.

 

[sparkwright]

You should not extend wires in a redundant back box and fill over as this will mean some of the wiring may be out of the 'safe zone' and get drilled through.

You can crimp wires together, but would have to be within the safe zone, the same width of the cable, so the wiring isn't out of the safe zone.

Usually one would join the cable in a ceiling void or under a wooden floor - but best to replace the entire length of cable if possible. Usually this is not always practical though.

No requirement for conduit, but will always recommend it for the reason you have already indicated.

Loose cable behind cabinets, a bit rough, should be clipped to the wall really.

The cable joints buried in the back boxes in the wall isn't acceptable, and there will be a better way of doing it.

Photos would be very welcome.

 

[vards01]

I wanted the boxes originally as you said flush in the wall and all cables chased and conduit. But I had 3 separate quotes and all said the surface mount box inside the cupboard was the way to do it. So I accepted that I was going overkill. The box is for a tumble drier in the next bay. There is a similar set up on the other side of the kitchen for dishwasher and washing machine.[/quote]

 

[vards01]

To be honest for the sake of unscrewing the backbox.....just seemed lazy to me. I do not think zoning would be an issue as the trajectory of the cable would remain the same.

Personally if I would of been doing the job it would have been joined up stairs under the floor as there is a good access point. I thought joints had to be accessible.....

 

[EFLImpudence]

as the trajectory of the cable would remain the same.

That's what I meant.

I thought joints had to be accessible.....

Screwed joints have to be.

There are maintenance-free junction boxes without screws now.

 

[vards01]

As this is a rental property I want it to be done properly. NIC electrician and reading the comments so far doesn't sound like there is anything which doesn't conform. I have never seen so much easi-fill!!!

 

[vards01]

This is my fault as I should have given a full specification. I'm now left with an unserviceable job..........if ever any remedial wrks need to be done the whole wall and tiling will need to come off. Live and learn!! Need to decide whether to rectify this now or let it go.........before the kitchen goes in.

 

[sparkwright]

You imply some of the wiring may be from the 60s.

Though it may not necessarily need rewiring, by doing joints under the floor above will at least mean new wiring is in the wall, and wouldn't need to be disturbed for a very long time.

Joints in walls, even done to regs, still strikes me as rough.

Though joints under floors are considered inaccessible, they are even more inaccessible in walls.

As we can't see the work done, it may have been done to rule, but something tells me probably not.

If you have the chance to get this redone, I would certainly take it.

 

[vards01]

Also seems to me to many radials coming off the ring....is there a limit for this? With appliances like washing machines dishwashers and tumble driers.....this doesn't seem quite right to me.

 

[securespark]

Radials?

Or Spurs?

If Radials, the answer is none!

Historically, the number of unfused spurs allowed was not to exceed the number of points on the circuit.

If more than one outlet is to be wired onto a spur cable, the string of sockets must be first fused down to 13A maximum so as to limit the total load drawn by that number of sockets to 13A.

It is better to design every point on the ring final (if indeed it is a ring final!) rather than spur off.

 

[vards01]

Sorry spurs.....I.e. no cable coming back out of the socket

 

[sparkwright]

You certainly don't want spurs comong from the socket that's getting plaster over, as three wires in a crimp don't go.

 

[ericmark]

Hi all,

I have just had some electric works done and wanted to check a few things were all above board.

Can you extend a cooker circuit by joining the cable (crimping), old 60's style metal switch backbox left in place new cable joined to existing inside this and filled? Two points here is it OK to leave the backbox in the wall and join the cable in this manner, when carrying high loads?

This is no different to using a joint kit crimped cables in epoxy resin in a box there are some points like ensuring box is earthed since metal and directions of cable if the box is hidden the box would show anyone doing work there is a cable running to it if covered would anyone realise there is a cable?

Is it a requirement to use conduit in a chase, or is it permissible to cable clip to the wall and plaster straight in. (basically means wrecking the wall if ever the cable need to be replaced.

No you can bury cable as it is as long as stuff around the cable will not leach out the plasticiser in the cable. In fact with the restrictions on buried cables and earthing metal in the wall using the old tin capping is now something which could be considered as not complying and the plastic stuff is hard to plaster over because of the way it flexes. In real terms you can't replace cable behind capping. Conduit maybe but even then the oval conduit it really hard to pull two cables into so normally still would require some re-plastering. Using Ali-tube would be best option but most people don't what to pay out for that cable.

Similar to point 1...but with a standard socket moving it down......joining (crimping) cable then filling in leaving the original back box in place.....plastic one this time.

Again no problem however although there is no requirement with older properties to comply with the 450mm to 1200mm rules to move out of those parameters a cable that was within them originally may be considered as not complying with building regulations if you have asked some one to break the rules then no law will cover you one can't have a legal contract for an illegal act.

Having loose cable around the back of kitchen units, should point out when the kitchen is installed you cannot access the cable as it is behind the units, the purpose of this is to allow surface mount socket to be affixed inside cabinet.

This has been talked about many times, to cleat a cable also means should anyone knock in a nail or drill it will not move and be damaged and not to cleat can also cause problems with weight etc. I am sure the Guide to regulations gives distances between cleats but it's only a guide not a regulation and one hopes an electrician will use common sense.

Really just wanted some confirmation this is standard practice, as I would have done it differently myself. But not being an electrician this isn't an option these days.

There is nothing stopping DIY although some things can end up more expensive to DIY what depends on where you live. The problem with DIY is inspecting and testing and filling out minor works needs test gear which is expensive so in the main not done. 9 times out of 10 no problem but should there be a problem by time you find out it's too late.

 

[ericmark]

Sorry got disturbed in middle of writing and a lot more info arrived between start of witting and posting.

The words spur and radial are confusing, and spur can be fused spur where the fuse is at the origin where it splits from the 32A ring or radial or unfused where the fuse is at the destination in the plug the latter is limited to one device.

I sometimes think the whole thing is written to confuse where a ring final circuit is not the final circuit where fused connection units are used but supplies another circuit.

It means that it becomes hard to work out what is being said so I'll return to basics.

The fuse protecting a cable is normally at the origin and with a 30/32A fuse/MCB/RCBO you need either 2 x 2.5mm² or a 4mm² cable. As one branches from the twin 2.5mm² or a 4mm² cable then either a fuse is put at the origin (FCU) or at the destination with the latter it can only feed one device.

Once a FCU is used there is no limit to number of devices.

The rules do not only cover domestic so in a factory one could have a ring with junction boxes and a spur from each junction box but each box or socket can only feed one device i.e. no more than three wires in each terminal.

Trying to without seeing to decide if an electrician has followed all the rules is hard we tend to quote rules like no more spurs that sockets on the ring but although generally correct as seen above there are exceptions.

What worries me is we can tell you it's all wrong and miss something vital.