Leaky Dimmers

lilricky

Active Member
If this has been covered before please send me there, I couldn't find it.

I'm attempting to to plug 4 small led work lights into a 4ch dimmer pack. It appears the dimmer pack leaks a little current even when off. 1/2 of the leds glow ever so dimly. I've used other packs from different manufactures with the same results. Interestingly, I've also used a larger version of the lights on the same dimmer packs without any of those effects. They come on/off just perfectly.

Any ideas/thoughts on a solution?
 
If this has been covered before please send me there, I couldn't find it.

I'm attempting to to plug 4 small led work lights into a 4ch dimmer pack. It appears the dimmer pack leaks a little current even when off. 1/2 of the leds glow ever so dimly. I've used other packs from different manufactures with the same results. Interestingly, I've also used a larger version of the lights on the same dimmer packs without any of those effects. They come on/off just perfectly.

Any ideas/thoughts on a solution?
@lilricky I hate to be the one opening this can of cantankerous evil worms, I know better but I'm still too naive to but out. Try plugging in a standard 120 volt 60 watt incandescent lamp as a dummy load on each of the relevant dimmers on your four pack. This MAY address your immediate symptom but totally flies in the face of why you shouldn't be powering your LED's via your dimmers PERIOD. (Oh I can feel the pending descent of the wrath I've attracted.)
Toodleoo!
Ron Hebbard
 
Thanks for opening Pandora’s box. I’m open to alternatives. I’m just trying to momentarily flash these things.
 
I think the dummy "ghost load" is your answer. People encounter this issue a lot when trying to dim LED rope light and even some low-wattage incandescent lamps. Dimmers generally have some leakage by design, and that's just enough to light some of the LEDs out there these days.
 
I think the dummy "ghost load" is your answer. People encounter this issue a lot when trying to dim LED rope light and even some low-wattage incandescent lamps. Dimmers generally have some leakage by design, and that's just enough to light some of the LEDs out there these days.
@lilricky and @Les Ghost loads are often magic when it comes to powering and dimming old-fangled neon signs. While an amateur, ghost loads were my saviors for powering neon beer signs from the 1950's on the sets of amateur productions. Once I'd risen to the heady level of head construction electrician in an IA scene shop I found myself having to light multiple 40 plus foot lengths of neon on a set built for a Tommy Tunes production entitled 'Best Little Whorehouse Goes Public' which I gather opened to scathing reviews and closed within hours of its official opening performance featuring scenery by Hudson Scenic incorporating custom neon by Robert Pupella of Toronto's NeonFX. I may be mis-remembering the scenery designer's name but John Arnone is the gentleman coming to mind. Lighting design was by Jules Fisher assisted by Ms. Peggy Eisenhauer who was an absolute joy to work with.
Toodleoo!
Ron Hebbard
 
There's a neat little device Elation makes that allows you to run LED strings (like rope lights) on dimmers. Now sells under the ADJ brand. Someone sawed one apart and posted pictures on another thread and it is actually more complicated inside then any of us thought is was! It does appear to work though. https://www.musiciansfriend.com/pro-audio/american-dj-led-dummy
Lot of places sell them. They all appear to be about $20.
 
Hmmm, the wheels are turning. I definitely have a use for some of these.
Is there a controllable relay or something other than a dimmer pack that would provide a momentary on/off?
I just happened to have extra dimmer packs on the shelf.
 
Hmmm, the wheels are turning. I definitely have a use for some of these.
Is there a controllable relay or something other than a dimmer pack that would provide a momentary on/off?
I just happened to have extra dimmer packs on the shelf.
You would need to find something that had mechanical relays that actually physically interrupted the circuit as compared to a dimmer pack operating in "relay" mode.
 
You would need to find something that had mechanical relays that actually physically interrupted the circuit as compared to a dimmer pack operating in "relay" mode.
@lilricky and @JD You can find such products by searching here on Control Booth manufactured by Doug Fleenor, or Johnson Systems (Not to be confused with Johnson Controls or Gray Interface or possibly LEX products (Excuse me, I'm dating myself) but you'd best sit down and be prepared for comparative sticker shock.
Toodleoo!
Ron Hebbard. [Attempting to gracefully herd the worms back in the hermetically sealed can.]
 
@lilricky I hate to be the one opening this can of cantankerous evil worms, I know better but I'm still too naive to but out. Try plugging in a standard 120 volt 60 watt incandescent lamp as a dummy load on each of the relevant dimmers on your four pack. This MAY address your immediate symptom but totally flies in the face of why you shouldn't be powering your LED's via your dimmers PERIOD. (Oh I can feel the pending descent of the wrath I've attracted.)
Toodleoo!
Ron Hebbard

It's perfectly fine to plug LEDs into dimmers. As long as they're designed with that in mind. The LEDs themselves won't care at all, it's really about how well the electronics are able to handle it.
 
Once again, I appreciate all of the suggestions. Just trying to make something work. As they say"why buy something when you can make it for twice as much"
 
For me the "Just make it work" method would be to add a resistor as a dummy load. An incandescent bulb works fine for testing but a resistor is less breakable and easier to make finger safe. A few cheap parts I might consider depending on current draw are:
1 Ohm 2W resistor, $0.25/each, probably fine for < 1A max draw
1 Ohm 5W resistor, $0.43/each, for something around <2A max draw
2.7 Ohm 10W resistor, $1.25/each, wouldn't use for more than 1A max draw, but would drop more voltage than 1 Ohm resistors.

A 60W incandescent lamp should have something around .5 Ohm resistance that's why I'm choosing values around 1 Ohm. If you need to adjust any of that just keep in mind that Power = (Current)^2 * Resistance, and round down very judiciously because AC peaks at 170V to ground and you have a high duty cycle .


EDIT: I can't do math apparently. Left with strikethrough since the next 5 posts give better advice.
 
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Ahhhhh... 1 ohm on 120 volts would pass 120 amps for a total output 14,400 watts.
 
I believe.. that some dimmers -- though I don't know about shoebox dimmers -- have or can be configured to have "keepalive" current being passed through to keep your filaments from being smacked with full inrush current cold; could that be what you're seeing?

Might there be a knob to turn it off?
 

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