2 gang 1 way wiring help needed

[SingingLaura]

We are rewiring a double dimmer to a double switch and have tried to reconnect wires as were previous but it is not working. Each switch just works one light. We have 3 wires all with 1 red, 1 black and 1 earth. Please please can you tell us where they go? Thanks

It has L1, L2 and L3 at the top and the same at the bottom!

 

[ban-all-sheds]

Are there any markings on the back (e.g. a diagonal line) to show which L1/L2/L3 are grouped together? The three for each side of the switch might be in a row, or a triangle.

When you've worked out which is which, you need to connect the red to L1 & the black (which should have red sleeving) to L2. Or L3 if the switch is then "upside down".

Earths (sleeved g/y) should go to the terminal in the back box if the switch is plastic, or to the earth terminal on the switch if it's metal (and then another length of earth wire run from there to the back box.

 

[SingingLaura]

Thanks for quick reply shall have a look and then probably come back screaming. Seriously thanks it is driving me nuts.

 

[SingingLaura]

Hi - so does each wire from either light get wired that way and if so what happens to the third wire from the mains?

 

[GaryMo]

Were all the blacks connected together in the old configuration, possibly in a connector block?

 

[SingingLaura]

yes

 

[GaryMo]

In that case, again connect all the blacks together in a connector block.
Connect the incoming red (from the mains) to L1 on one of the switches. Fit a link between this L1 terminal and the L1 terminal on the other switch.
Connect each of the remaining two reds to L2 of each switch (no link between).

Follow the advice above regarding earthing.

 

[SingingLaura]

Thank you - it works and you are lovely.

 

[GaryMo]

Glad to help

 

[SingingLaura]

OKAY - now everything works but since re connecting earth to back of switch - which was not connected the first time I tried ( and they worked) the switches work in opposite directions!

I hope this makes sense.

 

[333rocky333]

Move the wire from L2 to L3 if the switch is working upside down

 

[ban-all-sheds]

Having failed to read the OP properly, and missing the bit about there being 3 cables I should probably just shuffle away.

But WTH.

It's hard to see how connecting an earth wire can change which way round a switch works....

 

[securespark]

It's hard to see how connecting an earth wire can change which way round a switch works....

You should have been with me a couple of years ago on a fault-find. The supply to a boiler was mysteriously reversing polarity. Turned out to be a fault on a two way switch..... when the switch was in one position, the polarity was OK, in the other, it was reversed. Don't ask me how, we never did quite get to the bottom of it, but that's how it was!!

VERY strange..

 

[GaryMo]

OKAY - now everything works but since re connecting earth to back of switch - which was not connected the first time I tried ( and they worked) the switches work in opposite directions!

I hope this makes sense.

Did you twist the switch whilst connecting the earth thereby re-fitting in an upside down position?

 

[SingingLaura]

Thank you everyone - shall have a look.