Ceiling cord switch

[John]

I replaced a rather stiff cord switch for an elderly friend today. The existing switch wasn't particularly old.

The installation must be 60's or earlier. It has an old brown Wylex unit with wired fuses.

The switch had a neutral on the earth terminal. Clearly wrong, but was it ever a convention to loop in a neutral to a ceiling switch? An extractor is also fed from the switch. Therefore there were 3 blacks on the earth terminal, and two reds on each side of the switch (incoming live was looped in).

Obviously I am concerned - but if left alone I can't see a danger to it. When the house eventually changes ownership a rewire will be required as there are signs of some even older fittings.

What do you think?

[Andy Wade]

There's nothing wrong with routing the neutral through a switch enclosure if it suits the physical layout of the wiring to do so. (The technique's sometimes called the 'switch feed' system of wiring.) Obviously any terminal used for connecting neutral wires together must be insulated to the same standard as for 'live.' This clearly rules out using the earth terminal in a metal box for the purpose. With most plastic boxes though, you'd be OK.

The obvious question in your case is if the earth terminal was used for neutral, then how are the earths (CPCs) connected? Or do we deduce that the age of the installation is such that there are no earth wires to connect? If the latter then that is a cause for concern, and as you say, re-wiring is indicated in the not too distant...

[John]

Thanks - no evidence of earths on this circuit. The feed to the extractor had one that had been cut off. I think the fan was fitted less the 10 years ago.