Control/Dimming Another post about switched dimming...

Brentgi

Active Member
Let me start by saying that I'm not here to ask why or why not put your LEDs/Movers/whathaveyous on a switched dimmer. I understand the reasoning and am in the camp of DON'T DO IT.

With that being said...

In December of last year, we replaced our house lights, previously Altman scoops, with Chroma-Q Inspire's. They are amazing fixtures and we couldn't be happier.

At that time, we plugged them in to the same dimmer pack (Smartpack wallpack, installed) and just set it to full intensity, switched mode, because we were short on time. The plan was to have maintenance come back trough and remove the dimmer pack and install breakers for these fixtures. Days turned into weeks, and weeks turned into months.

I've brought up my concerns several times regarding the use of a dimmer pack (even in switched mode) for powering such devices. Not to mention, we could put the pack to use elsewhere.

At this point, I'm asking for technical materials explaining the possible pitfalls of such practices. My plan is to send it to the facilities director to have this project prioritized. After all, we don't want to be replacing an expensive fixture(s) when the correct solution comes at a small price, both in parts as well as labor.

If you can point me to any pertinent material, your help is appreciated. Thanks!
 
Search SSR relay and that will point you to a lot of threads that have to deal with the pit falls of using dimmers to power movers.

It's one of those things that will work til it doesn't and it's to late.
 
Although the rule of thumb is Don't do it, and given the option, I would never do it, there is another side to the coin:
Many modern power supplies, especially switch-mode supplies, are designed to work with some really crappy power. Best example of this is back-up power supplies for computers (Switch-mode supplies) which output a stepped square wave and most computers work just fine. The real problem comes with movers that use magnetic ballasts. These coils really need that nice slope to build up their magnetic field, and when fed a squared off waveform turn into high voltage flyback transformers!
The bottom line is; When in doubt, contact the manufacturer. I am sure they will give you some nice text or document information that you can pass on to your facility about why NOT to do it. Or, they may say, "Ehh.. no problem."
 
Let me start by saying that I'm not here to ask why or why not put your LEDs/Movers/whathaveyous on a switched dimmer. I understand the reasoning and am in the camp of DON'T DO IT.

With that being said...

In December of last year, we replaced our house lights, previously Altman scoops, with Chroma-Q Inspire's. They are amazing fixtures and we couldn't be happier.

At that time, we plugged them in to the same dimmer pack (Smartpack wallpack, installed) and just set it to full intensity, switched mode, because we were short on time. The plan was to have maintenance come back trough and remove the dimmer pack and install breakers for these fixtures. Days turned into weeks, and weeks turned into months.

I've brought up my concerns several times regarding the use of a dimmer pack (even in switched mode) for powering such devices. Not to mention, we could put the pack to use elsewhere.

At this point, I'm asking for technical materials explaining the possible pitfalls of such practices. My plan is to send it to the facilities director to have this project prioritized. After all, we don't want to be replacing an expensive fixture(s) when the correct solution comes at a small price, both in parts as well as labor.

If you can point me to any pertinent material, your help is appreciated. Thanks!

Unfortunately for your "court case", the fact is that "If it works, it works." The particular combination of fixtures and dimmers seems to work, so just relax. It's highly unlikely that there will be cumulative damage to your fixtures.

ST
 
Unfortunately for your "court case", the fact is that "If it works, it works." The particular combination of fixtures and dimmers seems to work, so just relax. It's highly unlikely that there will be cumulative damage to your fixtures.

I did end up finding documentation on the dimmer that says the dimmer in switched mode is unregulated. So, after all, it really doesn't matter as long as the dimmer is in the correct configuration.

It sounds like he's not as worried about damage at this point. He wants his dimmer back and needs backup for the argument!

You caught me. I do want those channels back. That's for sure.
 
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Every design of dimmer in "switch" mode will be a little different. "it will work fun until it does not" is usually something people say when they know something is not a good practice, but they don't actually understand why.

If you are actually concerned about the quality of the power, you can view the waveform on an oscilloscope. If you really just want your dimmer pack back. Tell them that maintenance was supposed to already have done the swap, and it is a waste of money tying up equipment that needs to be used else ware. Basically they are using $1000 dimmer in place of a $5 breaker; that seems like a poor utilization of resources.
 

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