Dodgy wiring

[sparky1508]

Hi all,

Changed some standard pendant lights today and the wiring was a bit dodgy.

The first light I looked at had 3 red ( normal ) 1 switch line ( normal ) but 3 neutral and 2 cpc. One I the cpc was sheathed in black and connected in the neutral of the light a continuity check confirmed it was connected to earth.
Second thing the light is on 2 way switching and in the first switch was 3 reds connected together 1 of which was from 3 core and cpc which went to the common of the second switch. 2 strappers yellow and blue in the correct place. There is 2 blacks in the first switch connected together and I disconnected them and checked and one was continuous with earth so when connected they both are. I disconnected the whole lot in the switch and ceiling rose and ran an IR test. L - N >500 Mohm
L - E >500Mohm
N - E failed.
Can anyone shed some light on this or is this a danger. My thoughts are that the earth in the light fitting shout not be connected to the neutral at any time and also is this likely to liven up anything connected to earth. His circuit is not on the RCD either.

 

[westward10]

Without more info as to why this has been done all sorts of scenarios are possible, I would concentrate on resolving the issue.

 

[Lagentium]

How old is the installation?

 

[sparky1508]

How old is the installation?

About 16 years or so I think

 

[sparksburnout]

is this an idiots guide "how to be an electrician"??

 

[sparky1508]

is this an idiots guide "how to be an electrician"??

Not sure what you mean??????

 

[sparksburnout]

Not sure what you mean??????

Sorry I might have misunderstood, are you an "electrician" doing this for a paying customer or just mucking about with your own electrics?

 

[sparky1508]

Sorry I might have misunderstood, are you an "electrician" doing this for a paying customer or just mucking about with your own electrics?

Here you go. What's the answer.

 

[sparky1508]

Not worried about switch 2. Ceiling rose and switch 1. Black sleeved cpc is continuous with earth and so are the 2 neutrals at the switch. Please teach me as to why it is wired this way.

 

[sparksburnout]

Not worried about switch 2. Ceiling rose and switch 1. Black sleeved cpc is continuous with earth and so are the 2 neutrals at the switch. Please teach me as to why it is wired this way.

You might need to ask one of the moderators but there is a trainee section you can post this sort of thing in, sorry I thought you were an actual electrician from your profile.

 

[sparky1508]

You might need to ask one of the moderators but there is a trainee section you can post this sort of thing in, sorry I thought you were an actual electrician from your profile.

I am a newly qualified domestic installer. I am assuming you dont know the answer either then as you haven't given one. Without taking the whole circuit apart and checking every length of cable to see what goes where it's impossible to know what is going on. Clearly I'm the idiot and you must be the guide from your comment so please guide me.

 

[sparksburnout]

Well, you may find it a bit disappointing to realise that very often in the great world outside the training room there will be all sorts of non-standard, strange, bodged, lashed up and generally quite confusing wiring arrangements. Lighting circuits are often in this category, and, I would say, amongst the worst. I have heard that more guys are killed working on lighting circuits (in domestic environments) that anything else, not sure myself but can well believe it. At the end of the day I would not try and attempt to work it out from a description or smoke-packet type drawing, what you need to do is employ your inspection and testing skills to determine whats is going where and what needs to be done to sort it. You may well have to take the whole circuit apart if that is what needs to be done, welcome to the wonderful world of domestic electrics!!

 

[sparky1508]

Ok thanks for the insight. In the meantime I will investigate further.

 

[sparksburnout]

Ok thanks for the insight. In the meantime I will investigate further.

That's what it boils down to mate. You will spend hours poking around some grotty loft trying to work out what some DIY'er has cobbled together, and yes, sometimes you will be better off starting from scratch, time-wise. I'm not trying to be funny, it's just how it is. The only relief is when you give them the bill.........

 

[Midwest]

Agree with sparksburnout, my fare is kitchen & bathroom refurbishments, but spend most of my installs putting right the DIY of yesteryear, should be a law against it, DIY that is


PS still no like button?

 

[sparksburnout]

Oh and as a footnote pinching the CPC for various uses is quite a favourite of the DIYer and even some "electricians"!!