So I Went Around My New Mates House For A Coffee...

[OnlQQker]

He was in the middle of decorating his new house, I only met him a couple of months ago and he seems like a really nice chap.

Anyway in the lounge one of the electrical socket face plates had been unscrewed from the wall for decorating. The house is 1920's and the wiring looked brand new in this particular socket.
Long story short a few months ago he had a spark from checkatrade to put in 3 new sockets. This one socket had a metal back box which had no earth from the backbox to the socket. I said to him that I had always been told they must be earthed in case the wiring frayed and this become live when the socket was away from the wall.

Anyway afterwards he phoned the electrician and he said it was an old back box and had no earth terminal in it, but I thought that just adding a washer to the screw that attaches it into the wall and treating it like an earth strap would work. Or am I just barking up the wrong tree altogether?

I then had a quick look at the fuse box, it's one of them old wylex ones with the fuses that you add the wire yourself when it blows. No RCD protection and signs of melting around one of the 32 amp fuses.
I determined one 32 amp fuse did the upstairs ring and spurred off for the immersion, the other 32amp did the down stairs sockets. The third 32amp which was melting did the cooker so I went into the kitchen to have a look.
My mate then said that they always smelt burning from the fusebox when the cooker was on. The cooker cable also supplied all the kitchen sockets and outside garage. 6 in total that were visible.
I asked what else they had on when the cooker is going, he replied, 'the washing machine, tumble drier and microwave and occasionally the kettle'

So I kind of said just don't use anything else when the cooker is going and this needs to be sorted asap as this is probably the reason the fuse is getting hot, it didn't help either because the fuse had what looked like a 16mm copper tail strand in it, I went to toolstation and got the correct fuse wire.

I'm surprised the spark who put the sockets in did not notice the melting 32amp fuse, it was very noticeable.

Anyway are any of you here covering Leighton Buzzard. If not can you recommend anybody that does cover this area?
He is having an extension built shortly which is going to need a few sockets and lights in it as well!

Thanks in advance...

 

[davesparks]

Anyway afterwards he phoned the electrician and he said it was an old back box and had no earth terminal in it, but I thought that just adding a washer to the screw that attaches it into the wall and treating it like an earth strap would work. Or am I just barking up the wrong tree altogether?

Yes you are barking up the wrong tree, earthing the backbox is not necessary as long as it has one fixed lug, it will be earthed via the screw holding the socket plate on.

Relying on a screw in a wall plug is not an acceptable means of making an electrical connection.

 

[OnlQQker]

Yes you are barking up the wrong tree, earthing the backbox is not necessary as long as it has one fixed lug, it will be earthed via the screw holding the socket plate on.

Relying on a screw in a wall plug is not an acceptable means of making an electrical connection.

I didn't get a picture so I found one online similar, so this is ok then?

 

[littlespark]

I don’t know what that last picture is, but it doesn’t look ok.
when the plate is screwed back, I don’t see any metallic connection from the back box, through the screws to plate, and then to the cpc. There’s no metal around the fixing holes of the plate.
Some old boys did just wrap the wire round a fixing screw, but the right way would be to drill and tap a hole, fit an M4 earthing stud.

it sounds like not earthing the box is the least of his worries.... but luckily you saw this and thought to investigate a little further.

Said it before, and I’ll say it again....
Never trust a tradesman that come through check a trade.... they use the Lone Ranger as their theme song.... biggest cowboy there is!

 

[pc1966]

My mate then said that they always smelt burning from the fusebox when the cooker was on.

WTF!! How can anybody not see that as a massive red flag saying "something needs fixed here!"
[automerge]1595921805[/automerge]

I don’t know what that last picture is, but it doesn’t look ok.

I don't think that is showing a UK socket anyway.
[automerge]1595922005[/automerge]

it sounds like not earthing the box is the least of his worries.... but luckily you saw this and thought to investigate a little further.

Agreed. Also the back box is not such a worry as normally it would be earthed via the fixing screws and is not normally acessible with power on.

I would be more worried about the opposite - earth/CPC to back box and no wire to the socket's terminal. That has a high risk of a poor connection and so maybe not disconnecting under fault as desired (more so without any additional protection from a RCD).

 

[littlespark]

I think the grey part could be a socket?? But on that particular plate shown, yes, the back box does need an Earth as there’s no connection from the terminal through to the screws.
I would think all UK sockets have metal around the screw holes, whereas light switches don’t. (No earth terminal on the plate, must use the back box)

 

[pc1966]

@OnlQQker get your mate to have a proper electrician in to check this out ASAP.

It might be just a bad connection in the CU but given the dodgy wire you replaced I suspect someone has fitted a cooker that needs more than 32A and/or it is also loaded with other stuff (i.e. not just a cooker/kettle circuit).

Again, this illustrates why I don't like the rewirable fuses, they are often rewired incorrectly. Short of a CU change you can get this sort of thing:

Wylex 32A SP Type B MCB - Screwfix

Order online at Screwfix.com. Modern alternative to fuses for Wylex Standard Consumer Units. Single pole, 230V AC, B curve, 3kA MCBs. FREE next day delivery available, free collection in 1 minute.

www.screwfix.com

They won't solve the lack of RCD protection risk, but they are massively easier for most folk to deal with if something trips and less risk of "oh stuff this bit of wire in, it will be OK" happening.

 

[magnoliafan89]

I think the grey part could be a socket?? But on that particular plate shown, yes, the back box does need an Earth as there’s no connection from the terminal through to the screws.
I would think all UK sockets have metal around the screw holes, whereas light switches don’t. (No earth terminal on the plate, must use the back box)

If there is nor fixed lug no earth fly lead and the accessory is plastic its apparently according to NICEIC and nappit not even a code.

 

[OnlQQker]

Thanks for all the replies

It's all going to need sorting out so like I said before if anybody here is covering the Leighton Buzzard area then please drop me a line.
He is going to need a new consumer unit, new earth to water mains and gas as it's only 6mm, sockets and light switches checked throughout the house. And new circuits running for a future extension. Also the cooker is going to be changed to gas so not sure if a lollipop circuit can be installed on the 6mm cooker cable or will need a new dedicated circuit altogether. I'll leave that decision for the electrician once I find one!

I would rather somebody from here do the job or at least a recommendation to somebody that knows what they're doing and test/sign off after all works complete.

@littlespark Thanks for the info regarding drilling a hole and fitting a
an M4 earthing stud. Like I said above the picture is a copy online that resembles the socket I saw in his house that day. The only difference is that the wiring to it has been renewed but no earth attached to the galvanised back box.

@pc1966

WTF!! How can anybody not see that as a massive red flag saying "something needs fixed here!"

I said exactly the same, but because he had an electrician in to do these 3 new sockets he assumed everything was ok. Still he has a wife and young child so I still can't work out why he left it frying.