Ghosting dimmer pack

I have 4 ld 360 leprechaun dimmer backs that when turned on and pluged into the board stay at 10% or so when they read 0 on the board. I tried adjusting the trim and that did nothing. I can bring them up brighter then 10% but no lower. Tried also connecting a terminator to the end of the chain and that did nothing either. Please advice
 

gafftapegreenia

CBMod
CB Mods
What board and what is the wattage of what you are dimming?
 

gafftapegreenia

CBMod
CB Mods
Leviton innovator. Wattage is only 5 watts a string (led Christmas lights) i am also having the problem if I have a source 4 plugged in as well. Tried changing the profile on the board as well and that did nothing

Hmm. I know the Leprecon's don't like to dim low wattage loads to a complete blackout, thus LED strings will ghost, but you say a Source 4 is ghosting as well. If you have the necessary parts, try swapping components. Try the board on another dimmer, the dimmer with another board, that kind of thing.
 

JD

Well-Known Member
Leviton innovator. Wattage is only 5 watts a string (led Christmas lights) i am also having the problem if I have a source 4 plugged in as well. Tried changing the profile on the board as well and that did nothing

We all know about the LEDs, they will not black out without a ghost load. The S4 not dimming is an indicator or a problem. So, lets divide and conquer! If disconnecting the board will black them out, then the problem (or setting) is in the board. Many boards let you establish a trim setting as well. Since the dimmer will black out, we know the dimmer trim is ok.

Board manual- http://www.google.com/url?sa=t&rct=...sg=AFQjCNHBbVWReINmqBuKq_eF7DPnNAZlDA&cad=rja

You may want to default the board back to it's factory settings.
 
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FatherMurphy

Active Member
If these are the older LD-360 dimmers (dark gray/light gray), not the newer ULD-360 units (all black), then the main circuit card runs on 0-10 vdc analog, and there are trim pots on the card that might need to be tweaked to cure the ghosting. DMX versions of these dimmers used a separate input card to decode DMX to analog, the main card stayed the same.

If the dimmers are ghosting with the 575 watt load connected to the problem channel(s) while the console is unplugged, then the onboard trim pots are the first thing to try. If the ghosting disappears when the console is removed, then the problem is likely the console, as noted above.

Adjusting the pots does involve working on the dimmers' innards while power is applied, if you're not comfortable doing this, please find a local service center to handle it for you. There isn't any way to do it with the case closed. If you've got a couple days, I'll try to find time to dig up the schematics and walk you through it, or you can call Leprecon at (888) 422-3537.

In 15 years of working on Leprecon stuff, this would be only the second time I've encountered LD-360 trims drifting.
 

David Ashton

Well-Known Member
does the dmmer hae one of those stupid "preheating" settings on it?
 

JWilsonLX

Member
Nothing to add solution-wise, but this same thing happened to me earlier this year with one of the old UL360s. 900w incandescent load, though ghosting was slight enough to not be noticeable without getting right up to the lamps. Also, ghosting persisted even when signal was completely removed.
 

David Ashton

Well-Known Member
have you checked for an earth loop especially if the case of the plug is connected to pin 1 earth,
 

cbrandt

Well-Known Member
I don't know if this applies to the ghosting problem, but I just fixed one of these. Had a very odd problem with the dimming curve. Ended up the IC that was controlling the phasing was bad. Swapping it around caused all sorts of weirdness. Really cheap problem to fix though. Just a standard LM324 IC. You can get the manywhere for less than a dollar.
 

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