Wrong light switch?

Jan 19, 2005 11 Replies

I have purchase some light switches, but instead of having 2 terminals they have 3 (SW1, SW2, Common). It seems they are intended for places that have 2 switches (ie. top and bottom of stairs).



Is there any way I can use these as normal switches, and if so which way round would I wire them?



Also - when replacing plastic switches (where the earth is wired to the wall casing) with metal switches, I assume that the earth should be connected to the switch not the casing?


Use Common and SW1.

You should wire to both. The circuit earth should go to the metal faceplate and a separate flying lead should go from the metal faceplate earth to the backing box. All earths must be sheathed in green/yellow, and must not be left bare.

Christian.

Just use Common and *one* of SW1 or SW2 (ignore the other one)

Use common and L1. If the switch operates 'upside down' use common and L2.

The best way is to move the earth to the switch earth terminal, and run a similar earth wire sleeved in the same way to the box terminal.

is in necessasry to do the latter if the box is plastic, or only if it is metal?

On Wed, 19 Jan 2005 22:17:32 +0000, Andy Burns strung together this:

Only when the box is metal.

IMHO, only metal. But it does no harm if plastic.

I suppose the earthing points on the placcie ones are more effectively just a physical anchoring point ...

On Thu, 20 Jan 2005 23:08:06 +0000, Andy Burns strung together this:

Yep. Some accesories say something along those lines on them.

A suitable place to make off the earth in an all plastic switch and box installation in case of future metal switch etc installation. Many simply cut off the EEC, and taping it up isn't so sanitary.

Oh if they were even that. Most plastic boxes have dispensed with such a useful 'add to cost' altogether :-(

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required