Control/Dimming Flashing dimmer pack

[Loren97]

I have a 6 channel elation hybrid dimmer (DP-640) pack at my church. It has recently started "flashing" during the service. I have 575w pars and Altman 360's hooked up to it, one per channel. It seems like several channels were affected at different times, but just one channel at a time goes to full bright and then returns to its normal level. Does this mean that the pack is toasted or is there a fix to this issue?

At one point we had 1000w lamps in the fixtures and were getting a lot of flashing, but after talking with a factory tech, we reduced the loads and the problem went away. Occasionally two of these packs, located on opposite sides of the room (but addressed the same) will flash the same channel simultaneously. We only have the lights on for about three - 4 hours each week.

I have a Jands Stage CL light board in the control booth and a dmx splitter 30' away in the balcony.

Thanks!

 

[JD]

Occasionally two of these packs, located on opposite sides of the room (but addressed the same) will flash the same channel simultaneously.

That one statement eliminates the packs as being the problem. Can't rule out the board, but sounds more like a DMX problem, specifically noise. Plenty of threads on that topic, chief suspects, bad cable, ground loop between packs/board etc, dirty connector, un-terminated line. Any new RF in the building?

 

[RonHebbard]

I have a 6 channel elation hybrid dimmer (DP-640) pack at my church. It has recently started "flashing" during the service. I have 575w pars and Altman 360's hooked up to it, one per channel. It seems like several channels were affected at different times, but just one channel at a time goes to full bright and then returns to its normal level. Does this mean that the pack is toasted or is there a fix to this issue?

At one point we had 1000w lamps in the fixtures and were getting a lot of flashing, but after talking with a factory tech, we reduced the loads and the problem went away. Occasionally two of these packs, located on opposite sides of the room (but addressed the same) will flash the same channel simultaneously. We only have the lights on for about three - 4 hours each week.

I have a Jands Stage CL light board in the control booth and a dmx splitter 30' away in the balcony.

Thanks!

I have a 6 channel elation hybrid dimmer (DP-640) pack at my church. It has recently started "flashing" during the service. I have 575w pars and Altman 360's hooked up to it, one per channel. It seems like several channels were affected at different times, but just one channel at a time goes to full bright and then returns to its normal level. Does this mean that the pack is toasted or is there a fix to this issue?

At one point we had 1000w lamps in the fixtures and were getting a lot of flashing, but after talking with a factory tech, we reduced the loads and the problem went away. Occasionally two of these packs, located on opposite sides of the room (but addressed the same) will flash the same channel simultaneously. We only have the lights on for about three - 4 hours each week.

I have a Jands Stage CL light board in the control booth and a dmx splitter 30' away in the balcony.

Thanks!

@Loren97 Questions:
Out of the Jands into the splitter.
Out of a driven output, not a loop of the input, and into one of the packs. Optimistically you're then terminating the loop output of this dimmer pack. You're either terminating this pack's output or you're routing it over to the input of the other dimmer pack which would be O.K. but unlikely as you've got the DMX splitter.
Here's what I suspect you are, ought to be, doing:
Out of the Jands, into the DMX splitter.
Out of one of the splitter's driven outputs, into either of the dimmer packs. Terminate the output of this dimmer pack.
Out of another one of the splitter's driven outputs, into the other dimmer pack. Also terminate the output of this second dimmer pack.
Live it up! Take a third terminator and terminate the looping output of the DMX splitter's input.
Reviewing:
The console drives the DMX splitter's input and this line is terminated at the loop out connector in parallel with the splitter's input.
One of the splitter's actively driven outputs drives one of the dimmer packs and this line is terminated at the dimmer pack's loop out connector in parallel with the first dimmer pack's input.
Another of the splitter's actively driven outputs drives the input of the second dimmer pack and this line is terminated at the loop out connector of this second dimmer pack.
Three lines with each line driving one device and each line terminated.
All lines are DMX cable. None of the lines are microphone cable.
So far so good? Questions?? Disbeliefs??? Debates????
Edit 1; Adding an alternative:
If you wanted, as an alternate, you could have connected the output of your Jands console to the input of either of your two dimmer packs then extended from the first dimmer pack's looping output over to the input of your second dimmer pack where you'd have either terminated the run at the second dimmer pack's looping output OR continue from the looping output of your second dimmer pack to the input of your DMX splitter.
With an eye to the future, I'd have gone with the previous arrangement.
With this second arrangement, you'd only have one run and one termination. The board's output would have only seen two devices (The two dimmer packs) plus one termination or three devices if you include the DMX splitter on the end of the run for future expansion.
Either way.
Toodleoo!
Ron Hebbard.

 

[Amiers]

What intensity do you have them set at?

 

[JD]

Don't forget, not all DMX splitter/isolators are created equal. Cheap ones do not isolate the ground between the outputs, thus a ground-loop problems could persist.
Simplify things. Put an opto-isolator between your board and one pack and a terminator on that pack. No problem? Then start adding components back in until the problem starts up. It doesn't mean that when the problem starts up the last unit added was bad, it only means that your issue reached the tipping point.

 

[Loren97]

Ok, this is helpful. I do have DMX cabling that runs from the board to the splitter, which is optical. From there it runs out to three different packs. From one pack it goes to several LED's while the others are the end of the run. I will order some dmx terminators and see if that makes a difference.

While I'm here, can you help me understand why portable packs are affordable and install dimmers so expensive?

 

[RonHebbard]

Ok, this is helpful. I do have DMX cabling that runs from the board to the splitter, which is optical. From there it runs out to three different packs. From one pack it goes to several LED's while the others are the end of the run. I will order some dmx terminators and see if that makes a difference.

While I'm here, can you help me understand why portable packs are affordable and install dimmers so expensive?

@Loren97
Assuming you can solder, terminators are pennies a pop. Whether you live in a 3 pin or 5 pin DMX world. A terminator is nothing more than a 120 Ohm resistor soldered across pins 2 & 3. An 1/8 Watt resistor is plenty, or a 1/4 Watt if it's all you can get your hands on. Most of the cost of the terminator is the cost of the connector.
As to your second query:
Usually, though not always, shoe box dimmer packs are built to a price point and the point is too often as cheaply as possible. I haven't gone shopping for years but I know Leprecon used to market some REALLY solid and reliable packs for which they charged appropriately. Install dimmers are usually, though not always, built to a better quality level.
Dinner time. Got to go.
Toodleoo!
Ron Hebbard.

 

[JD]

To expand on the Shoe-box vs Rack dimmer:
1) Modular construction- Racks generally are built modular which makes servicing easier
2) Abuse resistant- You will find threads on here about Triac replacement on Shoe-box dimmers and how little headroom there is on them to handle inrush and shorts. Rack dimmers are far more conservative in their choice of better parts and higher device ratings for a given power level.
3) Reliability- You may hear about a lot of problems on this forum, but remember, people come here when they HAVE a problem. Per installed channel, rack dimmers are far more reliable.
4) Country of origin- Many of the shoe-box dimmers are imports with questionable quality control.
5) Support after the sale- The installed dimmer market demands very good customer support. If far exceeds the support you are likely to have from a shoe-box manufacturer.
6) RF noise filtering- Dimmers produce a lot of RF noise. The filtering systems on rack based dimmers tend to be less compromised then the systems on shoe-box dimmers which by their very nature have to fit in a smaller space.

 

[FMEng]

A dimmer rack acts as a power distribution panel. Few buyers factor in the total cost of an additional circuit breaker panel and receptacles needed to power a bunch of shoe box units. If they did, that dimmer rack might look pretty cost effective.