Insteon 1000w dimmer with only 75 watts used? Is that safe?

[RichTJ99]

Hi,

I purchased to many 1000w dimmers & not enough 600w dimmers. Can I use a 1000w dimmer in a situation where the wattage is much lower (75w bulb being controlled)?

Is there a problem (aside from a waste of 20 bucks in the difference of price of the 600w to 1000w dimmer)?

Thanks,
Rich

 

[MikeB]

No problem.

 

[Herdfan]

Break all the fins off and you hava a 600W dimmer.

 

[RichTJ99]

Break all the fins off and you hava a 600W dimmer.

Im a little lost, the extra large fins are all that make it a 1000w dimmer? I had a hard time fitting a 1000w dimmer next to a 600w dimmer so I took the fins on the side off to make it fit correctly. Did I make that 1000W dimmer into a 600w dimmer by taking the metal fins off the side?

 

[MrGibbage]

Afraid so.

http://www.cocoontech.com/index.php?showtopic=5857

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[MikeB]

Im a little lost, the extra large fins are all that make it a 1000w dimmer? I had a hard time fitting a 1000w dimmer next to a 600w dimmer so I took the fins on the side off to make it fit correctly. Did I make that 1000W dimmer into a 600w dimmer by taking the metal fins off the side?

I believe taking off 1 side makes it an 800w dimmer. But I could be wrong, I never purchased a 1000w dimmer.

 

[ctwilliams]

Im a little lost, the extra large fins are all that make it a 1000w dimmer? I had a hard time fitting a 1000w dimmer next to a 600w dimmer so I took the fins on the side off to make it fit correctly. Did I make that 1000W dimmer into a 600w dimmer by taking the metal fins off the side?

I believe taking off 1 side makes it an 800w dimmer. But I could be wrong, I never purchased a 1000w dimmer.

If you break a side off of a 1000 dimmer then you must derate it by 200w. If you place a dimmer next to another dimmer you must also derate it 200w. So, in your case you have what amounts to a 600w dimmer. If you broke both tabs off and it is next to another dimmer you have a 400 watt dimmer.

I think thats right, at least that is what I have gathered from the long discussion over on smarthome.

 

[Digger]

Im a little lost, the extra large fins are all that make it a 1000w dimmer? I had a hard time fitting a 1000w dimmer next to a 600w dimmer so I took the fins on the side off to make it fit correctly. Did I make that 1000W dimmer into a 600w dimmer by taking the metal fins off the side?

I believe taking off 1 side makes it an 800w dimmer. But I could be wrong, I never purchased a 1000w dimmer.

If you break a side off of a 1000 dimmer then you must derate it by 200w. If you place a dimmer next to another dimmer you must also derate it 200w. So, in your case you have what amounts to a 600w dimmer. If you broke both tabs off and it is next to another dimmer you have a 400 watt dimmer.

I think thats right, at least that is what I have gathered from the long discussion over on smarthome.

Your math works for me......

This is the same with almost any dimmer out there.

 

[RichTJ99]

Hrmm, so does that mean a 1000w - both fins removed = 600w, then sitting next to another dimmer makes it 400w, inbetween both dimmers makes it 200w (from the original 1000w)?

A 1000w dimmer with one fin removed is 800w, then sitting next to another dimmer is 600w?

How about a Keylink (600w) in a two gang box with another dimmer 600w (both = 400w)?

 

[MikeB]

I think thats right, at least that is what I have gathered from the long discussion over on smarthome.

{slaps head} Thanks for correcting me. I knew I was missing something.

Hrmm, so does that mean a 1000w - both fins removed = 600w, then sitting next to another dimmer makes it 400w, inbetween both dimmers makes it 200w (from the original 1000w)?

A 1000w dimmer with one fin removed is 800w, then sitting next to another dimmer is 600w?

How about a Keylink (600w) in a two gang box with another dimmer 600w (both = 400w)?

Yes, I believe that's the case.

One thing, though - keep in mind that this only applies if the switch is carrying a load, and if it's a dimmer.

If you have a 1000w dimmer next to a 600w dimmer on a 2-gang box, you'd have to break the fins off 1 side, making it an 800w dimmer, then subtract 200w because it's next to another dimmer. HOWEVER - if the switch next to it is not carrying the load (say it's a 3-way setup), then you don't have to de-rate 200w, so the 1000w dimmer is an 800w dimmer.

If the 1000w dimmer is next to a relay, it also stays an 800w dimmer.

Someone correct me if I'm wrong.

 

[sknaf]

What about the case where you put the dimmers in a closet in a fancy dimmer box, and just have the scene selectors in the walls for use ?

Do the boxes still require derating, or do they have enough air gap to compensate ?
Seems to defeat the purposed a bit if you put all the dimmers in a closet dimmer box,
and then need to chop half the ratings off or purchase overrated.

- Knaf

 

[Herdfan]

What about the case where you put the dimmers in a closet in a fancy dimmer box, and just have the scene selectors in the walls for use ?

Do the boxes still require derating, or do they have enough air gap to compensate ?

It all depends on how much air can circulate. If they can remain cool, then you should be fine. Pictures?

 

[gregoryx]

Confirming and adding: I went through this exercise WRT the X10 Switchlinc 1000w units, which were nearly identical in terms of fin-removal and de-rating with multiple units in a box. Removing wings just lowers ratings as they are simply heat-dissipating fins. Humor note: I can't find a link now, but ya gotta see the PCS 2000w switch fins... HUGE! I'll also confirm the derating... went through that discussion with design engineer guys years ago; gotta be really safe on your UL rating approvals.

I may have "pushed" the rating limits a bit here and there - assuming full power and all units on at the same time and such - with both V1 (X10) and V2 (Insteon) based on the "heat is the ultimate measure" concept. They have been physically reliable - or at least as much so as any other SmartHome / SmartLabs switches - and have not started fires.

Back to the original question: running lower power on a higher power rated switch is NEVER a problem in this type of application.