Install lighting - dimmer suggestions

[Shane Presley]

I'm looking for some opinions on some workhorse dimmers- here's the scoop. Old church has become community center, and has 24K of PAR 64 1K's, and 12 lekos. They rent the room out to orchestras, theatre performances etc... and these people usually leave the lighting on for rehearsals and performances often the same day for about 6-8hours straight. I have installed leprechon LD2400 dimmers (2.4 per ch, 6 channels). I was un-aware that they intended on using the dimmers for "regular lighting" other than for show lighting. Obviously they are going thermal and shutting down. Does anyone have any suggestions for a cheap ( add-on) solution... They did have a CD80 pack, back when they just had 24K, (previous vendor), and they didnt' mention any drop out... Do you think that would be a decent "fix" to this solution, other than a full out install rack ( which is obviously cost prohibative)... Keep in mind the available power is 200 amp single phase. I'm thinking using CD 80 pack for the 4 bars of 6, and using only 2 leprechon packs to carry the 12 lekos...leaving 2 leprechon packs as "spare".

 

[Milt Hathaway]

Re: Install lighting - dimmer suggestions

I've never ever had LD2400 dimmers "go thermal", no matter how long they were in use, and I'm in a part of the country where 105 degree ambient is not unusual.

Is it possible there are airflow issues, or are the dimmers located where they are starving for fresh air?

 

[Tim McCulloch]

Re: Install lighting - dimmer suggestions

We got rid of our LD2400s because they'd thermal, but they came to us used and abused so I can't say with certainty that we'd have had the same experience if we had purchased them new. There are thousands of them out there, still working, so I think our experience was more unique than ubiquitous.

Shane, the CD80 packs are almost bullet-proof. I think your idea is a good one. I'd also consider Milt's comments - you may need to provide positive ventilation for the 2400s as that 'fixed' the thermal problems for us (most of the time). I suspect the way ours were racked up did us no favors.

Have fun, good luck.

Tim Mc

 

[Shane Presley]

Re: Install lighting - dimmer suggestions

Thanks guys - as for the leprechon airflow... I made a plywood rack for them custom - air slots cut in the sides top to bottom, about 5-6" wide, right where the fan sections are. I know they exhaust out the front,and I have them paired (in other words two together, a single rack space, and two more together. They are together mostly because I have the power runs encased in the plastic weatherproof flex tubing ( at the request of the hydro inspector)... What I will do is adjust the tubing lengths, and seperate them from eachother, I think I'm getting some conductive heat transfer... I also have a dual 3 space rack fan, installed at the bottom of all the dimmers, blowing air OUT of the rack. I'm not sure this is aiding at all, any ideas on how to improve the air flow. I thought you reduce the effect of the internal fans, if you "force air" into the unit. The rack is located in the basement of the church, not in sunlight, in atleast a 10 degree cooler enviornment from the rest of the spaces...Also another thing which may or may not be related... The leprechon DMX-64 demultiplexer went down a couple weeks ago. it was repaired, but when I re-installed it, it would not push the dimmers to 100%. SO I adjusted the max trim on the dimmers (and it took a fair bit to get them to 100% output) - this was about 10AM sat - at 9:30 PM sat is when the call came in , that they were going thermal - the previous 6 months, they have not been a problem... Do you think I've adjusted the trim to the point where they are operating too hard ? Or just a coincidence that I had to adjust the trims. I suspect the demultiplexer had a component change, which is now not driving a full 10 volts for control. I already have a new dmx card coming from northlight systems, that I'll probably replace the leprechon demulitplexer.