3-Way Dimmer Dilemma

Yukoner777 · Apr 2, 2021

Hi all
I have a dimmable LED light fixture in my kitchen controlled by 3-way switches (neither is a dimmer). Supply goes into Box 1, located by the sundeck door. Box 2 has the other 3-way switch, as well as a single-pole switch for a separate fluorescent fixture. The wires to the lights both come from Box 2.

Unfortunately, the way I wired it (20 years ago), the LED fixture has to be turned on in order to also turn on the fluorescent fixture.

My question is, is there any way I can replace the 3-way switch in Box 2 with a 3-way dimmer switch, while still having "non-dimmed" power supplied to the fluorescent fixture?

[ElectriciansForums.net] 3-Way Dimmer Dilemma

Darkwood · Apr 2, 2021

Taking into account you are DIY here and my 35yrs in the trade, even I am struggling to understand your wiring diagram, you have mixed 2 methods of wiring expression here and thus it is somewhat confusing as well as possibly confusing terminology.

Can you reword your post using the common electrical terminology we use on the forum, noted you in canada so you may differ or not -

The number of actual switches on any given plate is called a gang so common ones are 1gang, 2 gang and 3 gang.
The number of places you can turn the same light/row on is call 'way(s)' IE the number of ways you can turn it on off, switches controlling the same light at both sides of the room would be expressed as 2-way lighting circuit, if you can control the same light at 3 point then it is a 3 way lighting circuit etc..

We also are missing a lot of info', you put supply on your drawing, does that refer to both live and neutral or you just marking the permanent live in there?.. basically where do the lights pick their neutral up, is it looped in the switches or at the fittings or a joint elsewhere?

PS - see if you can draw a more informative diagram too.

Soi disant · Apr 2, 2021

Darkwood said:
The number of places you can turn the same light/row on is call 'way(s)' IE the number of ways you can turn it on off, switches controlling the same light at both sides of the room would be expressed as 2-way lighting circuit, if you can control the same light at 3 point then it is a 3 way lighting circuit etc..

Not in North America.

Darkwood · Apr 2, 2021

Yes I edited that to note the OP is from Canada , but the forum uses these terms hence I laid an explanation out so we are all singing from the same hymn sheet, unless you can decipher that plan and help out.

Soi disant · Apr 3, 2021

Yukoner777 said:
Unfortunately, the way I wired it (20 years ago), the LED fixture has to be turned on in order to also turn on the fluorescent fixture.

You did this:

Yukoner777 said:
My question is, is there any way I can replace the 3-way switch in Box 2 with a 3-way dimmer switch, while still having "non-dimmed" power supplied to the fluorescent fixture?

Do this:

Darkwood · Apr 3, 2021

I believe the wiring plan he showed must be incorrect, yes I can guess they were 1 way and 2 way switches regardless of the OP expressing them wrongly, but my point is that this cannot be how they are connected otherwise the fluorescent would only operate when the LED's were switched on as it is picked up off the switch live.
I suspect the OP has got the plan backward and the LED should be where he said it was the supply and the supply is actually coming into the switch box 2, if this is the case then all he needs to do is fit a grid switch, worse case is chopping a deeper box in for the grid body to fit.

@Yukoner777

Your plan is wrong - the supply comes into box 2 and loops to each switch, your LED is connected to the wire coming out of box 1, fitting a grid switch allows you to have different kinds of switches adjacent and just connect exactly the same, you will need to specify a 2-way grid dimmer and also way up the dimmer size and that the LED drivers are dimmable to start with.

Soi disant · Apr 3, 2021

Darkwood said:
I believe the wiring plan he showed must be incorrect, yes I can guess they were 1 way and 2 way switches regardless of the OP expressing them wrongly, but my point is that this cannot be how they are connected otherwise the fluorescent would only operate when the LED's were switched on as it is picked up off the switch live.

Indeed....

Yukoner777 said:
Unfortunately, the way I wired it (20 years ago), the LED fixture has to be turned on in order to also turn on the fluorescent fixture.

Darkwood · Apr 3, 2021

My bad on that one, reading it off phone so actually missed that line and focused more on the wiring plan..

If the OP can access the Live and Switch wire it could be a simple resolve to swap them over, even easier if they both at at the fitting.. still a grid switch would do what is been questioned here but may need a deeper box chopping in and only would work if the wires can be swapped over like below.
The other way is to fit dimmable remote controlled LED lamps to the fitting, you can dim them directly by remote without changing any wiring.

Soi disant · Apr 3, 2021

Whatever style of switches he uses he has no permanent hot at Box 2, so he'll have to take one there.

Darkwood · Apr 3, 2021

I expanding on that I added a pic too but no need to teach you to suck eggs it was for the OP + alternative option too, depends if the Live and Sw are at the fitting or not or are accessible to swap over if not then remote controlled LED lamps.

Soi disant · Apr 3, 2021

AFAIK North American wiring practice has always been to loop at the switches, not the fittings.

His diagram exactly matches the description of how his lights behave.

We need him to return and confirm, but I'm pretty sure there is no permanent line at either light and there is no permanent line at Box 2.

Soi disant · Apr 3, 2021

By the way...

Yukoner777 said:
is there any way I can replace the 3-way switch in Box 2 with a 3-way dimmer switch,

You do realise that if you do that, and you turn the light on at Box 1, it will come on at whatever brightness the dimmer in Box 2 is set to?

Darkwood · Apr 3, 2021

Looking on the tinteweb it seems loop in to lighting points is common practice in canada but they also like us use the loop into switches sometimes too.

Darkwood · Apr 3, 2021

Soi disant said:
By the way...

You do realise that if you do that, and you turn the light on at Box 1, it will come on at whatever brightness the dimmer in Box 2 is set to?

Yes that is how standard dimmers are normally installed on a 2 way circuit otherwise we would only fit them on 1 way circuits which is very limiting, it ain't going to be a big issue to go across and choose the correct level once you turned the light on and moved across the room, it domestic after all and what are we talking about 5m away?

Yukoner777 · Apr 3, 2021

Darkwood said:
Yes I edited that to note the OP is from Canada , but the forum uses these terms hence I laid an explanation out so we are all singing from the same hymn sheet, unless you can decipher that plan and help out.

Sorry guys. What I mistakenly called a 2-Way switch is actually a single-pole switch. The 3-way switches are common terminology here.