Backwards switch on one side.

[sarah1406]

I had the plasterer in and he removed the switches/sockets in my home. I have a two gang switch one side controls downstairs light and the other controls upstairs. The upstairs works fine, up for off, down for on. But for some reason the bottom switch is the opposite.
This is how it’s wired:
Downstairs-
Red-com
Black-L1
Earth-earth

Upstairs-
Red- com
Blue- L1
Yellow- L2
Earth-earth

Any help would be appreciated

 

[ETAF]

if you swap the Blue-L1 and Yellow L2 around that should allow it to work the way you want
Yellow -L1 & Blue-L2

Make sure you isolate the power for the switch - its possibly on a different MCB - depending if the wiring is different upstairs and downstairs
SO be careful, the switch maybe 1 is on one MCB and the other switch on a different MCB , just depends how wired - so make sure Nothing is live before touching

The up stairs light - does that also have a switch upstairs - so when that is OFF -Up position in UK, then the downstairs has to be in the down position - ON for the light to be OFF
and I'm assuming that one is OFF postion

 

[sarah1406]

Thanks for your reply! Yeah the upstairs has a single switch also to control upstairs light but not really having any issues with that light itself

Will doing this fix the issue for the downstairs light because it’s that one in the wrong position (down for off and up for on)

Thanks again

 

[ETAF]

Will doing this fix the issue for the downstairs light because it’s that one in the wrong position (down for off and up for on)

should do

 

[Adam_151]

Will doing this fix the issue for the downstairs light because it’s that one in the wrong position (down for off and up for on)

To clarify, swap whatever is in L1 with whatever is in L2 on the switch that you want to reverse positions on.

 

[boringoldcodger]

should do

I don't believe that's correct.
If I've understood properly then it should be a case of moving the black wire from L1 to L2. But do be very careful as ETAF recommends.

 

[ETAF]

I don't believe that's correct.

I thought the bottom switch was part of a 2 way - with upstairs switch - because of the 3way cable , and downstairs was the other switch just for downstairs light - so a single on/off switch NOT controlled by another switch

 

[sarah1406]

Yeah that’s right, the downstairs side of the 2 gang only has three wires, live, switch live, and earth. The live is in com, switch is in L1 and earth is in earth. This is only to control one light and it’s the only switch what does so
Then in the other side of the 2 gang switch it’s to control the upstairs light (which also has another switch upstairs to control the same light) which has 4 wires, red, blue, yellow and earth

 

[ETAF]

2 way switching (3 wire system, old cable colours)

Circuit diagrams - Two way switching means having two or more switches in different locations to control one lamp. They are wired so that operation of either switch will control the light. This arrangement is often found in stairways, with one switch upstairs and one switch downstairs

www.lightwiring.co.uk

 

[JohnW2]

Yeah that’s right, the downstairs side of the 2 gang only has three wires, live, switch live, and earth. The live is in com, switch is in L1 and earth is in earth. This is only to control one light and it’s the only switch what does so
Then in the other side of the 2 gang switch it’s to control the upstairs light (which also has another switch upstairs to control the same light) which has 4 wires, red, blue, yellow and earth

Does the downstairs switch also have an L2 terminal (which is not being used)? If not you would have to physically turn the switch up the other way, and then swap the L1/L2 connections to the upstairs switch to restore the functionality you want.

If the downstairs switch does have an L2, just move the black wire (from it's current L1) to L2.

Kind Regards, John

 

[sarah1406]

yeah it also has a L2, I will give this a go after work, thank you and thank you to everyone else who has helped it’s appreciated

 

[JohnW2]

yeah it also has a L2, I will give this a go after work, thank you and thank you to everyone else who has helped it’s appreciated

You're welcome.

Kind Regards, John