sockets wired in 1.0mm 3 core flex

[Mark_Burgess]

they appear to be wired as a ring which i can connect into and i'm changing the CU so would i get away with a 20 A MCB?

How do you know they are wired as a ring, do the cables go back to the consumer unit on its own MCB?

I did a limited PIR before but didn't take every socket off the wall.Had no reason to suspect that it had been done in flex.I assume the homeowner either did it himself or a mate of the kitchen fitter did it. either way, it makes it difficult to remedy.

Did your limited PIR involve you looking inside the consumer unit?
If you answered yes to my first question above. You should have looked further into it and made the customer aware at the time, looks like you have shot yourself in the foot!

Down rate the circuit or you will have to remove the tiles, its an easy job to remove them with out breaking them.

 

[Geordie Spark]

How do you know they are wired as a ring, do the cables go back to the consumer unit on its own MCB?



Did your limited PIR involve you looking inside the consumer unit?
If you answered yes to my first question above. You should have looked further into it and made the customer aware at the time, looks like you have shot yourself in the foot!

Down rate the circuit or you will have to remove the tiles, its an easy job to remove them with out breaking them.

Not when I clag them on it isn't !!! :winkiss:

 

[Mark_Burgess]

Not when I clag them on it isn't !!! :winkiss:

I thought you northeners used chewing gum if the gripfill has run out!

 

[plugsandsparks]

The only thing i can think of is de-rating the breaker. would be wondering what the Zs is for the circuit as well. The main problem i suspect is going to be the potential for burning out the flex behind a socket and then losing the "ring" - then its just a matter of time.
Good news is that much of the equipment in a kitchen is high load short duration like kettles, microwave, toaster, but if there is a dishwasher in there or a washing machine and heaven for bid they use them at the same time, i just cannot see the circuit being fit for purpose.
I personally would look at the appliances in the kitchen and think would de-rating work, if not you gotta put in a thicker cable

 

[Geordie Spark]

I thought you northeners used chewing gum if the gripfill has run out!

Whey telt ye that lyke ???? ....... It's a lie .. we always use congealed beer oot o' th' drip trays from the club doon th' road man !!! ;
0

 

[Geordie Spark]

The only thing i can think of is de-rating the breaker. would be wondering what the Zs is for the circuit as well. The main problem i suspect is going to be the potential for burning out the flex behind a socket and then losing the "ring" - then its just a matter of time.
Good news is that much of the equipment in a kitchen is high load short duration like kettles, microwave, toaster, but if there is a dishwasher in there or a washing machine and heaven for bid they use them at the same time, i just cannot see the circuit being fit for purpose.
I personally would look at the appliances in the kitchen and think would de-rating work, if not you gotta put in a thicker cable

So far, I've resisted the temptation to post what I think about this utter balls-up but I can bite my tongue no longer.

The fact is that it is so completely unfit for purpose that the only solution for the OP is to rip it out & start again or walk away from the job.

As for the OP, If I had been him I would have been too embarrassed to even think of starting this thread.

Sorry bonny lad, but if you need to be asking what to do about this, I'm wondering if you've chosen the right career path.

 

[telectrix]

I thought you northeners used chewing gum if the gripfill has run out!

nah , they use gripfill if the chewing gum runs out.

 

[Geoffsd]

Geordie Spark is right. It is not allowed by BS7671.

However, if you were to note this as a departure and 'design' a 1mm² Ring Final Circuit - for some inexplicable reason - then

following the rules for a 2.5mm² Ring which, with a combined CCC of 54A (2x27), is only allowed a maximum OPD of 32A, a Ring with 1mm² flex which has a combined CCC of 20A would, by the same proportion, only be allowed a maximum OPD of 11.85A (20x32/54).

Therefore a 10A OPD would have to be fitted (only just enough for one 2kW kettle).

The circuit is completely useless and has to be replaced.

 

[Guitarist]

I deleted what I wrote earlier because I thought it may be taken as too harsh.

After several rewrites, I just cannot find the right words for this thread, so I will keep quiet on this one. :shocked3:

 

[Strima]

I deleted what I wrote earlier because I thought it may be taken as too harsh.

After several rewrites, I just cannot find the right words for this thread, so I will keep quiet on this one. :shocked3:

You feeling alright? Or have you spent too long in the sun?

 

[mayfair]

Well went to a job Thursday funny burning smell was the call anyway this villa has a pool pump house, a large recording studio, and a granny flat running of 1.5 mm three core flex spured of the back of a kitchen socket. The socket was where the funny burning smell was comming from btw. The flex is all plastered into the wall through the concrete floor then plastered again in a JB to feed the three above points....... Owner was unsure what i was getting at after a long explanation and drawing on the back of a beer mat............I was out of there so fast!

 

[Deleted member 26818]

why would a load need to be midway in a ring to avoid overloading??that's the point of a ring, that every point is the same in regards to any load upon it.I find that worrying that someone would think otherwise

If you place a 20A load on the midpoint of a RFC, 10A will flow down both legs.
If you place the 20A load a quarter of the way around the RFC, 15A will flow down the short leg and 5A down the long.
As the flex is rated at 10A, you should be able to see that having 15A flow through the cable is not good.

 

[ruston]

Has'nt a departure to be at least to the standard of safety afforded by the regs or to a similar standard............

If this is a recent installation it 's not up to that criteria ("Doing a re-wire for a customer who's had their kitchen redone recently ") no excuse at all in my opinion ,dose'nt comply with table 52.3 minimum cable size for power circuits 1.5mm, at the least.

 

[Guitarist]

You feeling alright? Or have you spent too long in the sun?

Must be the sun, mate. I really don't know how to respond to the op. Good job you guys were here in my hour of need....

 

[Strima]

Must be the sun, mate. I really don't know how to respond to the op. Good job you guys were here in my hour of need....

Just have a cold one and take a few deep breaths, it'll be alright...

 

[Adam W]

I don't see that there's technically anything 'wrong' with installing a ring final in flex, although I'd probably use double bootlace ferrules to reduce the risk of the ring breaking, and definitely reduce the rating of the breaker.

The question is though - 'why would you?' And for a kitchen as well? Given the amount of high current consuming appliances in a kitchen you'd want as much capacity as possible, not to restrict it by doing it in thin flex. When I say there's nothing technically wrong with it, that assumes there was a reason for doing it in the first place, other than it being cheaper or what the installer had lying around at the time.

I find it quite ironic that the OP is asking for serious suggestions for 'sorting out' such a silly circuit arrangement.

 

[JulianC]

Stick in a 6A breaker, remove the socket fronts and replace with batten lamp holders. Voila, novelty kitchen lighting and problem solved. No need to thank me.

 

[Marvo]

I don't see that there's technically anything 'wrong' with installing a ring final in flex,

Wouldn't the fact that there's no derating figures for different installation methods mean you can't use flex as installation cable?

 

[shocking_eg]

typical, sounds like kitchen fitters at work on the electrics :S

 

[plugsandsparks]

Well he's not been back yet, hope its a really small kitchen, otherwise his re-wire is going to have one circuit missing on his report.. LOL

Wonder what the max demand is ?

 

[Heisenberg]

Is it me or are there no de-rating factors for flex, or have I gone blind...

Is the stuff not designed to be free in air and only have some minor weight bearing capability for supporting lamp holders etc...

Or am I talking complete bollox...

Table 4D2A prehaps, and also taking section 2.4 in appendix 4 into account?? Not too sure. Guess a lot depends on the max working temp of the pvc insulation used.

 

[Adam W]

Wouldn't the fact that there's no derating figures for different installation methods mean you can't use flex as installation cable?

I'm not sure about 'rating factors' but the good book gives maximum current allowances for certain reference methods. Table 4D2A (thermoplastic insulated and thermoplastic sheathed) in the red book I believe?
From that, max 11A for a radial.
The way I see it, flex is similar to 'pre-wired conduit' and is technically acceptable provided you make allowances for things like putting ferrules on the ends of the cables.
On boats we use H07 flex for all the AC stuff, including sockets.

 

[Adam W]

... As Heinsberg pointed out.
Should really read the whole thread before posting.

 

[sedgy34]

Why don't you rewire what you have quoted for and note down of this 3core on kitchen ring in the farce box on your cert after all if customer doesn't want it changing you can't force the situation leave it alone

 

[cbw]

I agree ^^^^^ Staple to your EIC a danger notice

 

[Guitarist]

It could always be that this guy is a DIY'er, has wired his kitchen in what he had in the shed, and has since realised (or been told) that he's made a mistake.
He now wants solutions to the problem which won't involve him removing the tiles, and all he has been told on here is that it needs redoing!
Remember guys, we don't know anything about anyone who posts on here. It's only after a while that we begin to get a picture of who is actually qualified.

 

[TPES]

I had a job recently where the hole kitchen ring (7 sockets) was wired in 1.5mm and cable covered in plaster and tile adhesive going off on all different directions up the wall

 

[Guitarist]

It is really scary that these people are allowed to buy tools!

 

[Amp David]

Nice bit of skirting board on the kitchen worktop, lovely

 

[richy3333]

Nice bit of skirting board on the kitchen worktop, lovely

After the initial WTF looking at the wiring I spent 5 minutes asking myself why there is skirting board on the worktop?

I see the OP'S not been back after several pages of postings.

 

[cbw]

He is actually on here at present, also been a member since 2009 so probably a spark?

 

[Amp David]

He is actually on here at present, also been a member since 2009 so probably a spark?

then is asking is it ok to fit a new CU with a single RCD, because there's not enough space.

 

[cbw]

Big sigh..........

Fair play I was wrong, gave him benefit of the doubt though!

 

[SPARTYKUS]

then is asking is it ok to fit a new CU with a single RCD, because there's not enough space.

Not really a new thing is it that one, been around for 4 years now as a "no it's not"

 

[needasparks]

Nice bit of skirting board on the kitchen worktop, lovely

with lighting cable on the sockets and skirting on the worktop do you think the kitchen drawing was scaled wrong ? easy mistake to make.

TBH over the years i think i've come across the use of smaller cables being used the most incorrectly, perhaps if the sheds only sold 2.5 and up and done away with the smaller sizes may half the amount of bodges they do.

 

[Guitarist]

with lighting cable on the sockets and skirting on the worktop do you think the kitchen drawing was scaled wrong ? easy mistake to make.

TBH over the years i think i've come across the use of smaller cables being used the most incorrectly, perhaps if the sheds only sold 2.5 and up and done away with the smaller sizes may half the amount of bodges they do.

Maybe the shed only had 2.5mm T&E in stock, which is why the installer went for the 1mm flex

 

[Geoffsd]

Just realised that no one has queried that the flex actually is 1mm².

Has the OP, perhaps, made another mistake and got this wrong too?

 

[Rockingit]

You might like to point your customer in the direction of trading standards....this sounds like a right old bag of spanners. Electrically speaking I'd leave well alone, tell the customer WHY (if needs be give the phone number for BCO, always a good 'I know what I'm on about' tool) and let them get on with suing someone whilst you do the rest of the job.

 

[SPARTYKUS]

Maybe the shed only had 2.5mm T&E in stock, which is why the installer went for the 1mm flex

looks like 0.75

 

[needasparks]

The story does not say exactly who carried out the work other than it was wired so surely it must have been the owner.
I would think most people that have had a job done incorrectly would want their head on a stick and it corrected FOC but it seems they want it brushed under the carpet reading between the lines, more so as there has been no response from the OP.
There has been loads of regs thrown about trying to justify leaving this flex in place which we all know should not be done, even the OP knows it deep down, hence his asking. de-rating the circuit is no more than polishing a T##d.