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#110325 - 03/23/06 07:19 PM UK Electric Shower Violation
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Registered: 10/07/00
Posts: 3188
Loc: NY, USA
Quote:
FWIW, I'm not actually an electricial contractor, trying to get into training for the industry ATM, this picture was nicked from a UK forum

These things have a heater in (the black lump) that is rated at somewhere between 7kw - 11kw (thats at 240v BTW), if you look at the cable supplying it, and compare it to the internal cabling, you can see that its undersized, also flexible cable shouldn't be used for fixed wiring, and where it enters the unit without use of a gland, the watertightness is no more... also having the cable hanging loose in the shower area is... not good

- Adam_151
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#110326 - 03/23/06 11:57 PM Re: UK Electric Shower Violation
Trumpy Offline


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Registered: 07/05/02
Posts: 8560
Loc: SI,New Zealand
Gidday there Adam,
Welcome to the group!.
I'd like to say that there is no way that wiring supplying that unit will carry the current required to operate it.
We have the same units over here in New Zealand and nothing short of 6mm2 wire will do for a set-up like this.
I'd also be interested to see what sort of fusing was used at the feeding end.
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#110327 - 03/24/06 09:45 AM Re: UK Electric Shower Violation
chipmunk Offline
Member
Registered: 07/20/04
Posts: 142
Loc: Southampton, UK
Ouch. Just plain 'ouch'.

Notwithstanding the fact that flex can't be used for fixed wiring and it's majorly undersized, when it eventually melts down, if it doesn't short circuit right then, there are going to be exposed burned out wires in the shower area, not nice. I second Trumpy's wish to see the feed end of this, I bet it's just as scary (I am thinking either wired into a socket on a 30-32A ring, or more likely 13amp plug with a piece of nail as the 'fuse')
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#110328 - 03/24/06 12:53 PM Re: UK Electric Shower Violation
Texas_Ranger Offline
Member
Registered: 12/17/01
Posts: 2351
Loc: Vienna, Austria
Hm... guessing the wiring at the top is 6mm2 I'd say the home owner wiring is at max. 1.5mm2, rather 1mm2. OUCH!

Let me guess. The typical rating of such a beast is 7-9kW. Assuming a resistive load and an optimistic voltage of 240V that's 29-37.5amps. A 32A breaker probably wouldn't trip at all.
Go figure...
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#110329 - 03/24/06 03:36 PM Re: UK Electric Shower Violation
Trumpy Offline


Member
Registered: 07/05/02
Posts: 8560
Loc: SI,New Zealand
Chipmunk,
You're dead right, mate, that is a flex!.
Sorry, I'd forgotten that in the UK, all the fixed wiring cables are grey sheathed.(AFAIK)
This takes on a whole new meaning of wrong now.
I hope that this was disconnected when it was found, this could cause someone some real harm.

{Edit: I always thought that the supply cable was supposed to enter the bottom of the unit, through some sort of gland to maintain the IPX4 ingress protection rating?.}


[This message has been edited by Trumpy (edited 03-24-2006).]
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#110330 - 03/25/06 04:15 PM Re: UK Electric Shower Violation
Adam_151 Offline
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Registered: 03/07/06
Posts: 8
Loc: Lincoln, England
Quote:
Sorry, I'd forgotten that in the UK, all the fixed wiring cables are grey sheathed.(AFAIK)


Not exactly true, Twin & Earth which is used for most domestic wireing is usally grey on the outside, it was available in white as well, but as part of the colour change white T&E is the special low fume stuff, and grey is the normal stuff

years ago VIR (rubber) cables were used which were black on the outside, some modern cables are black, split concentric and SWA (steel wire amoured) are both black.

MICC can be bare copper on the outside, or can be white, orange, black, and probably many other colours besides, and firetuff is usually red (used for firealarms, so it can be seen at a glance what its for)

Different types of cable used in the UK can be seen here: http://www.tlc-direct.co.uk/Main_Index/Cable_Index/index.html
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#110331 - 03/25/06 11:04 PM Re: UK Electric Shower Violation
Trumpy Offline


Member
Registered: 07/05/02
Posts: 8560
Loc: SI,New Zealand
Adam,
Have you seen the area used by us guys from outside of the US?.
It gets a lot of use.
Check this out and enjoy .
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#110332 - 03/26/06 11:31 AM Re: UK Electric Shower Violation
RODALCO Offline
Member
Registered: 12/08/05
Posts: 865
Loc: Titirangi, Akld, New Zealand
I'm supprised that the 1.5mm² flex wire has not discoloured from heat yet, nor are the choc bloc connecters which have usually steel sleeves instead of brass in them.
If that is an 7 to 11 kW heating element, the fixed wiring should be at least 6mm². not a piece of flex.
I wonder what is on the other end of that flex. a 13 Amp plug with a drillbit as fuse?
you wonder sometimes that not more houses burn down or people get electrocuted.
The flex. earth wire looks like that it is not lugged off properly either.
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#110333 - 03/26/06 02:34 PM Re: UK Electric Shower Violation
Adam_151 Offline
New Member
Registered: 03/07/06
Posts: 8
Loc: Lincoln, England
You'd be supprised how much they can take, it'll get a bit warm and go brittle, but not start melting in a massive way, its amazing the tolerances things have...

On another note, I need to install one of these units at home (with 10mm² wire ), bloody regulations make it difficult for DIYers to do much these days, sorry, ranting
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#110334 - 03/28/06 03:55 AM Re: UK Electric Shower Violation
pauluk Offline
Member
Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Welcome to ECN Adam,

It also appears to me that the "entry point" for the undersized flex has been created by just hacking a hole in the side of the unit.

I thought it was bad when I found a shower wired from just the pull-switch to the unit with 2.5 T&E, but this one beats that by a long chalk!
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