Lighting circuit wiring concerns

Hi I have recently moved in to a house and wanted to replace the light fittings in my living room. In doing this I quickly found out that the loop in loop out method (which I'm familiar with) had not been used.

Instead the switch had been feed (I'm less familiar with this method). However what I found concerned me a bit, in that the neutrals that had been bunched in a choc bloc also had a conductor terminated to the earth terminal of the switch plate.

Is this normal? I'm thinking remove the conductor from the choc bloc to the back of the switch plate (red wire in attached pic) thereby leaving the neutrals bunched in the choc bloc, and then running a priece of earth cable from the back of the switch plate earth terminal to the patress earth terminal

Please advise if this sounds correct, or if there is any reason this original set up may have been done.

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No that's not correct.

There is a green wire there, the faceplate should be connected to that but you should ensure it is actually connected to Earth.

Either a mistake or an idiot or -

I can only assume the CPC (earth wire) is not actually connected to earth and someone has connected the neutral thinking it would be satisfactory.
If this is the case then you must replace the switch with a plastic one.

As you say leave the neutrals in the block on their own.

Looking at the lack of grommets and taped-up conductors, it will be well-worth getting an inspection done on your installation to see if there are any more horrors lurking 'neath the surface.

While an inspection will not expose every switch or socket box, some simple tests will show whether there are short-circuits like that.

Personally after seeing something like that i'd want the whole installation fully inspected (not just sample-inspected as is normal in a EICR).

Thanks for the replies guys. I have tested the whole lighting circuit for continuity of earth and all seems fine, apart from some switch lives not being sleeved on the upstairs circuit. I can not understand why this connection was ever made?

I am in the process of arranging a NICEIC approved Electrician to do a full test.

Thanks for your help.

It was an old trick used years ago. When there was no earth available they connected the neutral to the metal parts. It is no longer acceptable.

Basically, the earth wire connects to all exposed metal parts of an installation. The earth and neutral are joined together in the meter cabinet. If a live wire makes contact with the metal plate, the fuse will blow, preventing the box becoming live and causing you to get fried when you touch it.
In the absence of an earth wire it is better to connect the neutral to the earth terminal than nothing at all, but the proper way is to run an earth wire and keep the neutrals isolated. There is a good reason for this.

Get it all checked out by an electrician.

levstar said:

I have tested the whole lighting circuit for continuity of earth and all seems fine

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Not correct!!
If they are using a neutral as an earth you will always get continuity due to the fact that the neutral and earth are connected together in the meter cabinet.
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I have tested the lighting circuit and found that the neutral had only been joined to earth at this switch, this has been removed and tested using the wander lead method, and I have obtained good reads.

BTW: Thanks for the background on this, very useful. Cheers!