Wife shocked when halogen blew

[Siddell]

Please help diagnose:

Wife turns on understairs halogen spotlight (metal, earthed fitting). Light flickers, she gets a nasty shock and the rewireable lighting circuit fuse blows. Bulb has blown too.

I feel awful as I wired the light myself, but when I come to check it the live is not loose. What I do find is continuity between earth and neutral. Closer inspection reveals that this bridge appears to be upstream of the isolator, as the continuity only exists when the fusebox and the isolator are both on. I then check a plug socket and find continuity between earth and neutral there too, so it's the same all over the house presumably.

The odd thing is, my earthing arrangement is effectively TT at the moment: the only paths to earth are via water and gas. UKPN have installed a PME terminal but it is not yet connected to my earth block as supplementary bonding needs upgrading first, (this is a priority, I know). They did braid their cable onto their neutral but at no point does that braid or their cable get connected to earth. So really I ought not to have earth-neutral continuity upstream of the isolator as far as I can deduce. From the information I have, it is as though the neutral cable to the house is in contact with a gas or water pipe.

So my questions are:

1) Why might my wife have got the shock?

2) Why is there earth-neutral continuity?

3) Do I need to call UKPN urgently?

Thank you for your help.

 

[Siddell]

P.S. Light has been in place for over a year with no probs. Philips Twistline Alu 50W 240V.

PME terminal installed (but not connected) a while ago.

 

[polo1]

I would be calling a local sparks pronto. I'm guessing your TT is not effective and providing a high resistance. The DNO might get involved due to the planned PME, but they might also say they have not yet provided an earth so not their problem.

Regards

 

[Knobhead]

From reading your previous posts you need to call an electrician.
Carry on the way your going you’ll be paying for a funeral.

 

[Des 56]

Is this the typical case of "It works so it must be Ok"

Unfortunately electrical installation and its possible dangers usually only become apparent with increased knowledge

 

[Engineer54]

You don't have a TT system either, if you don't have a made electrode!! Your effectively relying on water and gas service pipes for the earthing of your property, which to my recollection is no longer allowed!!

Who knows what's downstream or upstream of your property, your gas and or water service pipes may be plastic either side of you, leaving you as an island as far as metallic pipework is concerned... Seen this at both a friends house and my sisters old house. Both were ex council houses...

 

[Knobhead]

ak47semi, you will keep waiting. Reported as spam.

 

[Taylortwocities]

Siddell.

Take a look on google at how electricity gets to your house - in particular how the connections get from your local substation to your house.

You see, neutral and earth are connected together at the substation. So, in the house, you will see a connection between earth and neutral, unless you disconnect the supply neutral.
You must, must do this before messing around with electricity - neutral is defined as a live conductor and mains voltage can appear on neutral conductors, unless you know what you are doing.

Probably best if you stop, now. You need to use an electrician, for everything.

 

[StuSpiers]

1) Because you have no earth and probably have a dangerous installation of said light fitting, as the home-owner it is your responsibility to provide electrical safety.

2) See post #9

3) No - just do what they told you to do!

Recommended:

Stop playing with death, you will be sent down if your wife dies next time.

 

[Siddell]

Thanks for all your input - you're completely right.

Events have really overtaken my understanding.

I'm gonna call an electrician.

 

[telectrix]

siddell, if you post your location, one of us may be near to you to sort it out.

 

[Siddell]

I'm in central Guildford, Surrey. If anyone is in this neck of the woods that would be ideal.

 

[Siddell]

I've booked in a very friendly local electrician to come and fit a new fusebox and inspect.

Thanks again.

 

[Taylortwocities]

Cool.

Make sure he is registered with one of the Part P schemes as changing the consumer unit is notifiable work.
In theory he/she should be on the list here
Competent Persons Register | Home

 

[Siddell]

Yep, found him. NICEIC registered. Thank you.