Control/Dimming - High Current low Voltage dimmers

[icewolf08]

Does anyone know if there are any DMX controllable 12V dimmers that can handle 35A? I would love to be able to do this project with a singer dimmer, but if I needed to go to two smaller capacity dimmers, I could work with that. So, if you happen to know where I can pick up such a device, please let me know!

[JD]

Usually would not suggest this because of TOS, but I know your background! Actually any old back-to-back- SCR (or Triac) dimmer will work with a little modification to the secondary firing circuit. (SSR's are potted so no such luck.) PM me. The "musts" are, it must be 12v ac not DC. It will also drop about a volt, so full output will be 11 volts. The other way would be to get one of those cheap DMX kits. (link slips my mind) and just strap a fat triac on it. Triac BTA@0 BTB@0 SBTA@0 SSAC Triac CN;JIA products

[Chris15]

The question of AC vs DC does need to be resolved before we can go much further...

I have some thoughts if JD hasn't solved your problem...

[otherwho]

ARTDC Dimmer
Controlling 4 by 50Amp independent dimmer channels with data supplied either using standard DMX

might be a solution if there still in business

or

might be able to build a custom solution from there DMX4dim-HO
RC4-Magic Wireless DMX & Dimming
RC4Magic DMX4dim-HO

[icewolf08]

Yup, I neglected to mention that it is DC... Right, I actually have a good relationship with the guys at TheatreWireless.com. I already own an RC4 system, but I didn't realize until today that they were actually making the high output dimmers yet. It was hard to find the info on their site, but Jim got back to me very quickly via email. Provided the money is there, this is the ideal solution.

[mrb]

I had something filed away which would do what you needed, ill try to dig it out.

[SHARYNF]

my suggestion would be to have the dimmer before you convert the ac to 12v dc this way you can tweak the level to 12volts with full on, and at about 4 amps ac you will have no problem getting a dimmer to handle the power.

Sharyn

[ajb]

my suggestion would be to have the dimmer before you convert the ac to 12v dc this way you can tweak the level to 12volts with full on, and at about 4 amps ac you will have no problem getting a dimmer to handle the power.

Sharyn

While you actually can do this with a transformer, phase chopping a transformer primary drastically reduces its efficiency, and you'll need to derate it to compensate for the added heating in the coils. Since the OP is already looking for 35A on the secondary, you're now looking at a very big transformer. A switch-mode converter would be more efficient and more tolerant, but it won't vary its output as its input changes (which is kind of the point of most regulated power supplies). And all that is moot if the OP is working from battery power.

[icewolf08]

This of course is all driven by battery, we don't want to trail cords on the scenery.

[dramatech]

northlightdmx.com has a four channel circuit board that takes DMX to pulse width modulation that can dim LEDs or run DC motors. As built, each channel of the board has a 2 amp MOSFET output. Call James Cart at 480-429-0577, and give him your requirements. He is very flexible at modifying his products for very little cost, and sometimes for nothing. He probably can give you info on a MOSFET that can handle 35 amps and supply a board that can connect to that MOSFET.

[mrb]

northlightdmx.com has a four channel circuit board that takes DMX to pulse width modulation that can dim LEDs or run DC motors. As built, each channel of the board has a 2 amp MOSFET output. Call James Cart at 480-429-0577, and give him your requirements. He is very flexible at modifying his products for very little cost, and sometimes for nothing. He probably can give you info on a MOSFET that can handle 35 amps and supply a board that can connect to that MOSFET.

thats the one I was thinking of.

[icewolf08]

Lots of interesting ideas to look into. Now I have to do some research.