Beginner trying to replace a ceiling switch

[Mike]

Hi,

The ceiling switch for my bathroom light (pull cord) recently broke, and I would like to replace it. I have obtained a new switch which seems pretty similar to the old one. I have three wires coming out of the ceiling: red, black and green/yellow (earth). The red wire is in a terminal marked "L1". I can't make out what the black wire goes into.

Does this setup ring a bell? Will it be a problem switching over to the new pull switch? I have a fair bit of experience with DIY, but not with any mains electrical stuff, so I was wondering how safe this was all going to be....

Many thanks, Mike

[Bernie The Bolt]

No, but it should turn a light on.

Bernie The Bolt

[The Wanderer]

How many terminals on the new pull switch? If there are only two terminals then the red goes in one, the black into the other.

If there are three, i.e. the pull switch is suitable for two-way wiring, there should be ambossed onto the switch 'Common' (or similar), in which case the red wire should go into the common terminal, the black wire into either of the remaining.

The new switch should preferably have a mounting pattress. There will probably be a terminal in the pattress for the earth wire, which will probably not be connected to anything else, as there's no provision for anything to be earthed on the switch.

I think that rather depends on whether you switch everything off at the consumer unit before you begin......[1]

[1] You are, of course, going to do that, aren't you? :-)

[Staffbull]

Should be C or Common for the neutral

[The Wanderer]

Err, there's unlikely to be a neutral at the switch - just a live and a switch wire.

[Staffbull]

Yep sorry meant "black" wire

[David Hansen]

On Mon, 02 Oct 2006 15:51:56 GMT someone who may be Mike wrote this:-

Coming out of the ceiling and into the existing switch? If so then the black wire undoubtedly goes to a terminal marked C, Com or Common. You should find the same terminals on the new switch. Connect the wires to the same terminals.

If the new switch has a terminal marked L2 then check the screw in the terminal is done up fully and then ignore it.

[Mike]

OK, I see a "common" on the new switch. I guess that's where the black wire goes...

It has L1 and L2, so good to know I can ignore L2.

Thanks for your help!

Mike

[Mike]

Erm, of course... ;) the consumer unit would be a fuse box to the uninitiated, would it?

Thanks very much for your reply, Mike

[John Rumm]

By rights, the black wire ought to have red sleaving or tape round it to indicate that it is really a live!

Or ignore L1 if you prefer, since with a pull switch you can't see which way is "on" by looking at it. The switch action is a "change over" type i.e. common is connected to L1 or L2 each time you switch it swaps.

So you start out like:

L1 #======== COM / ======# L2 #========

Then you switch to:

L1 #======== COM ======# \ L2 #========

[Mike]

Thanks for that! A picture is worth.....

:) Mike