Control/Dimming Controllable LED house lights

[NeroCaesar]

Hello, I am looking for advise on controlling my house LEDs with DMX.
Currently I have 30x cans with 31w Sylvania 30deg Par38 LED flood lights, I also have an 96ch EDI MX dimmer Rack.

What I would like to do is take the LED house lights that are currently hooked up to constant power 120v, and integrate them into my dmx system, while still having a switch on the back of the theatre to turn them on and off even if the board is off. If the cost is too high I can ditch the switch in the back of the house.

Currently I am sure if I hook up the Cans to a Dimmer module on the rack I will not get a smooth fade down. I have been reading a lot of descriptions and posts on here but iI am not sure they pertain to my situation. I was looking at something simple that Leviton or Lutron makes, but I am sure there is a cheaper solution for this one channel house light dimming option.

Thanks in advance,
-Greg

 

[microstar]

Several thoughts:
Are the Sylvania LED's listed as being dimmable?
If they are, can you test them on one of your dimmers with a small incandescent lamp added to try and smooth out the low end?
A remote preset station like the Fleenor PRE10A works well but a little pricey at around $500 for the remote.

 

[Bubby4j]

Could you also have a custom dimming curve in the dimmer rack? That might help smooth it out too.

 

[NeroCaesar]

Hmm they are dimmable, but I could try to fit one of the cans with an incandescent to help that out. I'll take a look at the Fleenor but that is a bit more than I wanted to spend on this project.

The I haven't played with the rack too much but it does have a Proportion and a Profile option... the manual doesn't describe too well how it works, but it is worth a shot.

 

[BillConnerFASTC]

You'll never get a smooth fade to full off with retro-fit LED lamps on a mains dimmer. At some point you'll be below the power supply - built into the lamp - threshold for working and it will blip off - or on. If you want smooth dimming to and from full off, you'll need a pretty sophisticated power supply in each fixture or perhaps remote. I can't help but believe replacing the cans with a new LED fixture - like an incito, PL1, D40, GDS, chalice, or other - isn't the only practical and most economical option - at around $1000 a fixture or more - but maybe there are LED lamps - not line voltage but 0-24 - in combination with a Pathway or Fleenor LED driver - that might work. Would never recommend that approach - just replace the fixture.

Ghost loads or perhaps replacing dimmer with something like a Fleenor DMX8DIM (one or more) might be better than your current dimmer, but still never like incandescent dimming.

Good luck. Maybe you'll be teh one to unearth the holy grail of LED conversions - but many have searched a lot and found it unlikely - or no more likely than tele-portation, as in "beam me up Scotty."

 

[RickR]

Most dimmer racks have a "panic" or emergency function to override the console. If yours has this you might hook up a simple wall switch as a "dry contact closure" to trigger it. EDI made several variations on the MX rack so you might have to dig out your manual. It's a bit of a clunky solution and could be a problem if the switch is flipped during an event.

I have seen references to single channel DMX wall plates but I don't know where to get one. I've also seen several variations on the Fleenor device but at similar or higher prices.

 

[BillConnerFASTC]

I apologize if I missed your point - but I thought good dimming was the quest. Should be many ways to have a local switch to turn on and off.

 

[NeroCaesar]

Bill you were right smooth dimming from the light board is the goal, and extra points is having an additional on/off by the entrance. I will look try looking through the manual some more for the kill switch.

I was hoping there might be a 700w+ dimmer for LEDs lights that run at 120v that I can't seem to find as well.

 

[sk8rsdad]

The physics of LEDs means they do not dim the same way as an incandescent lamp. Simply put, it is not possible to make an LED behave acceptably from zero-to-full using a dimmer intended for an incandescent lamp. They all bump on or off at some minimum power level.

AFAIK, nobody is making a retrofit dimmer that works with retrofit LEDs to provide the sort of dimming that matches the physics of an LED. I doubt it would be possible to get any sort of approval to push high voltage DC through existing wiring and fixtures intended for an AC load.

As has been suggested, the only way to get smooth dimming is to purchase fixtures with integrated dimming, and that is prohibitively expensive at the moment.

 

[coldnorth57]

at the space i work the school changed over to LED in the house light direct replace they dim (ok) but at 10% they blink off and same coming back on the only people it seems it bouther are the lighting techs. Now I do not know EDI MX rack but in my outher space i have the house lights run off a low voltage switch (CD80 rack) with a varible restor so they don't run full on all the time (set to 70%)

 

[Jay Ashworth]

The OP actually has 3 only semi-related issues:

1) Move houselights to DMX from hard switch
2) Get a good curve from that
3) Softswitch override.

Sent from my SPH-L720

 

[BillConnerFASTC]

Lets assume you there is no way that anytime soon anyone is going to pay a $1000 to 20000 per fixture plus data wiring if not wireless - probably a dollar wash but schedule - then retrofitting the Fleenor DMX8DIM is probably going to give you best performance for a mains (line voltage) dimming LED retrofit lamp. I don't know the lamp you use but the TCP ones seem to perform best - maybe getting that bump on around 5% rather than 10% - and the Fleenor dimmer is 8 channels at 240 watts per channel so probably will depend on your existing wiring be multiple circuits but that is likely if you have 30 cans that had 150 or 120 watts per can, and now 31 watts per can - but might require a little circuit work - but 30 X 31 = 930 watts - just half the channels - and I think that piece is around $750 list. Talk to a dealer. As far as switching - power from the switch that is there, run a DMX line to the box - not ideal but tenable - even if you have to replace switch with a key switch or put a locking cover over it. Call Doug Fleenor - he might be able to tell you how to do it even more eloquently than my use the big hammer approach.

1) House lights controllable by DMX - check
2) Get a good curve - define good but if lamp is decent than it won't be bad - but I wouldn't know without a sample of the lamp you are using
3) Rear of house on and off (yes - if it can be programmed to be at full with loss of DMX you have to leave console on or find a DMX output device that will do it.)

Or spend $40,000 or so.

Or not.

 

[JChenault]

We converted to retrofit LED par cans on a mains dimmer recently. There is a chop off at about 10% but we felt that for us the cost the compromise was worth it. (YMMV)

As others suggest, we use the Fleanor preset10 for control when board is off, and our emergency exit lights are a completely separate system. I can't say too many good things about the preset10.

In practice it is working pretty well. We fust don't do slow fades of our house lights, and choose to ignore the low intensity jump, and different lamps blinking out at slightly different times.

The dimming issue is not inherent to the LED part of the fixture but the power supply. When the mains power drops below some value it just cuts off all power to the LED. At some point someone will come up with a more intelligent power supply that energizes, and then starts putting out power slowly.

 

[microstar]

Just curious as to what issues you are having with your preset 10.

 

[BillConnerFASTC]

At some point someone will come up with a more intelligent power supply that energizes, and then starts putting out power slowly.

Maybe but I suspect it is neither economically viable to develop and produce a wide variety of retrofit lamps with high end drivers built in nor will it be possible given the realities of thermal management for the LEDs and drivers that come anywhere near the output of the original incandescent lamp in that fixture. Just look at a 500 watt quartz fixture and an LED fixture that has similar output - and the LED is generally much larger - and that's an enclosure carefully designed for the LED and heat - not just any old sheet metal can for a quartz bottle. Much more practical to develop a less expensive replacement unit.

 

[Dionysus]

I'd have to second pretty much everything everyone else has told you. Don't expect to get a perfect curve with your retrofit LEDs, especially at budget prices. Part of the give-and-take of using LEDs where systems are meant for incandescents.

LED replacement lamps are almost always larger as Bill said, can't count the times I've had trouble fitting them into fixtures in both new construction and renos. Also very rarely dim them.

Also agree with Bill that making an optimal LED replacement with a fancy power supply is just pointless and not cost effective. The Package would need to be too big. These days if you want LED you need to buy a dimmable LED fixture NOT a "LED Replacement Lamp for an incandescent fixture". But rarely do people want to lay down the money for them, to which I say "Do you want LED or not?" (well not in those exact words). Plus Im sure if actual LED fixtures sell better they will become cheaper (or so Id hope). I've installed a lot of very nice LED potlights that are beautiful.

As a frame of reference The Grand Theatre in London Ontario (Canada) has converted all house lights, hallway lights, etc to either LED or Fluorescent (mostly LED) in order to become more "Green" (and get a bunch of money from the government for the replacement lamps), this includes lights in some areas being triggered by occupancy sensors, etc. Most of the lights around the theatre are controlled by Strand A21 Architectural lighting control panels through the building however. But this does allow house lights to be controlled from the wall-switches. Work-lights have been even replaced with white LED fixtures (not "replacements"). The LED conversions of course still don't dim any better of course, they have the exact same issue. Now I am quite certain a solution like this is far outside your budget, hence why most everyone is suggesting using the Fleenor equipment (Id have to second that).

 

[JChenault]

Just curious as to what issues you are having with your preset 10.

No real negative issues. I did have to "customize" the back box wirh a grinder, aside from that absolutely no issues ( except that I only use two or three presets )

 

[JChenault]

Maybe but I suspect it is neither economically viable to develop and produce a wide variety of retrofit lamps with high end drivers built in nor will it be possible given the realities of thermal management for the LEDs and drivers that come anywhere near the output of the original incandescent lamp in that fixture. Just look at a 500 watt quartz fixture and an LED fixture that has similar output - and the LED is generally much larger - and that's an enclosure carefully designed for the LED and heat - not just any old sheet metal can for a quartz bottle. Much more practical to develop a less expensive replacement unit.

Well. The first thing we need is that high end driver. Then we need to see the comparative size and incremental cost. Not sure if the final answer would be a retrofit lamp or a new architectural fixture. From a marketing standpoint, you might sell more "100% dimable PAR lamps" that a new dedicated fixture. I expect that "mains dimming" will be with us for some time in the architecturL world however,

 

[microstar]

Same here on installing the Preset 10. Not much one can do on a retrofit except the grinder approach.

 

[BillConnerFASTC]

I expect that "mains dimming" will be with us for some time in the architecturL world however,

Certainly existing installs that are not more than 20 or 25 years old will predominantly not be changing in out. Likewise most existing chandeliers of note and similar significant lighting, may be retrofitted with new mains dimmers. New build however is becoming primarily solid state. We use to put 2 to 5 - 96 way dimmer racks in a high school, and in last 3 to 4 years probably not more than a 24 dimmer panel, with portable solo dimmers for 30-40% of the theatrical. (We are stuck on orchestra shells where the initial cost doesn't yet justify savings.) But going LED for house and work is a no brained, more than paid for by just whatever the cost of relamping is - catwalks, hoists, tracks, or maybe just labor and falls if no provisions are made.