Dimmer switches on same circuit

[bc]

I have 2 three-way dimmer switches controlling the same set of lights. Is this permissable? The switches are rated at 600w and my light capacity is at 510w. I also have 2 dimmers which control 2 different sets of lights mounted in the same box. Is this OK? I read somewhere that mounting 2 dimmers side by side reduces there wattage rating. The reason I'm asking is the switches seem very warm to the touch.

Thanks,
BC

[Troy]

I am not sure about the 2 three-ways controlling the same set of lights, but it sounds ok to me. You should be fine on the 2 dimmers side by side as well. I have noticed that generally they do run pretty hot. I don't know what is too hot, but you can expect them to generate some heat.

Welcome to the forum!

[irregularjoe]

Traditionally the normal configuration was a 3-way dimmer at one end and a 3-way switch at the other. However I understand that there are now 3-way dimmers available that can be used together without a switch. But they have to be the new type designed for this purpose, not the typical dimmers..... Slide dimmers usually have cooling fins (heat sinks) attached to the sides. To fit two dimmers side by side in a 2 gang box you usually have to clip the heat sinks off of one side. Hence it then is no longer rated at the top (600 watt) capacity. If your dimmer gets too hot you can always get a higher rated dimmer. 1000 watt is the next step up. A lot more cosltly though.

[Jimmer]

FYI... I just purchased and installed a pair of new matched 3-way dimmer switches. Very nice. No noticable heat from them. They were $69 for the pair. To turn on you have two choices... one tap and they turn on slowly to a preset level, push and hold for a second and they turn on full power. To turn off again two choices tap once and they dim off in a second or push and hold for a second and they slowly dim off over ten seconds (giving you exit lighting). Of course at any time you can adjust the light up or down at either dimmer.

They are about the size of a GFCI outlet so they pretty much fill a standard depth box, If I was doing a new install I would have used the deeper thermostat boxes for some extra room.

Hope this helps, Jim



'Just a handyman trying to help'

[JAFA]

Directions on some 3 way dimmers I bought, say only one 3 way dimmer can be used in a circuit. I have been searching and searching but can't find a reason for it. Any ideas why this would be? Could it be just the model of the dimmers? Also, I have ran across the same thing for other dimmers as well in my search. Yet no explanation as to why.

tony

[Jimmer]

Tony,

Welcome to the forum.

The way a set of three way switches work, standard "dumb" dimmers cannot work. The set that I refer to above are "smart electronic" in that they transmit to each other their setting and therefore you can dim properly from either one. They do not use 'slide' type but instead use buttons for up and down, a slide type could't work.

This is a diagram of how a standard 3-way switch works...



Hope this helps, Jim

'Just a handyman trying to help'