Wiring a 3 gang 2 way light switch

[gezkc]

Hi,

I've bought a new brass 3 gang 2 way light switch to replace the old (30+ year old) plastic one in my hallway, but can't figure out how to wire it.

The back of the old one looks very different to the new one (see pics), so I can't make sense of how to wire up the new one.

The old one has 5 terminals along the top with the 2nd terminal unused, and 4 along the bottom with the 3rd one unused.
The new one has 4 terminals along the top (marked COM, L1, L2, COM) and 5 along the bottom (marked L1, L2, COM, L1, L2)

Can someone make sense of this for me, as I'm really struggling!

Thanks!

Old switch

• gezkc
• 21 May 2012
• 1

5 terminals along the top (2nd one not used)<br>4 terminals along the bottom (3rd one noy used)

New switch

• gezkc
• 21 May 2012
• 1

4 terminals along the top (marked COM, L1, L2, COM<br>5 terminals along the bottom (marked L1...

 

[EFLImpudence]

Turn the new one upside down and they're exactly the same.

 

[riveralt]

As EFL stated when the new switch is turned upside down they are the same -
Except that since this is a metal switch it needs to have an earth wire linked from the switch to the earth lug at the back of the box - I take it there is an earth wire already attached to this lug - If not then you cannot use this switch.

 

[gezkc]

As EFL stated when the new switch is turned upside down they are the same -
Except that since this is a metal switch it needs to have an earth wire linked from the switch to the earth lug at the back of the box - I take it there is an earth wire already attached to this lug - If not then you cannot use this switch.

Yes, it does have an earth wire attached to the backbox, so that's not a problem. I just couldn't make sense of where the rest of the wires should go! If it's as simple as just turning it upside down, then I should be able to copy the way the old one's been wired.

Thanks for your help!

 

[securespark]

Attach a piece of 1mm2 to the switch earth terminal and the other end to the box terminal. Don't forget a bit of sleeving.

 

[ban-all-sheds]

If it's as simple as just turning it upside down, then I should be able to copy the way the old one's been wired.

Plan B:

Before doing this job, actually learn how lighting circuits work, actually learn what switches do, get a multimeter and learn how to use it, work out which terminals are which on the old and new switches.

 

[sparkwright]

You need to realise that each individual switch consists of three terminals. Each switch has one terminal at one end usually called common, and two terminals at the other end.

You must pay particular attention to copying each individual switch. Do one individual switch at a time. It is very important to put the same wire in the new common terminal, if you don't it will not work right.

Forget all that rubbish about what terminals are on the top row, and the bottom row. Work out which terminals are for which individual switch.