Control/Dimming 26 broken ETC dimmers

[Silic]

Hi well the problem is that we have two racks a sensor 94 and sensor 24 and currently the 24 rack is full of nonfunctional dimmers, There all D20. It is the dimmer cause we have to switch them out for different shows. When you send a signal to them the signal light turns on but there no power to the lights and the dimmers on the same power main work just fine. Some of the dimmers it is just one channel that's dead and both on others. The circuit breaker is fine i ran a continuity check with a mult meter. I think it is the power cubes, and power cube failures are rare. if it is the power cubes is there a way to fix them were a school theatre and close to being cut so we cant spend more money. But we need the dimmers fixed we already have 3 more dimmers ghosting. And we need them fixed for the upcoming shows.
Any ideas anything would be appreciated

 

[mrb]

power cubes must be replaced, they cannot be repaired. Of the things in a dimmer module that fail, the power cube is the most common. Contact dimmer.com for a repair estimate.

I am wondering how you managed to blow so many channels. Do you have some bad cabling with short circuits?

 

[Silic]

Thats the weird thing. I witnessed one die, it was powering house only 1000 watts were on that chan and then it started to ghost and then just died and it doesn't work any more. We had a repair estimate form another company it would be 2.6k which we don't have.

 

[Footer]

Sensor power cubes are about a hundred dollars each, give or take if you shop around. One power cube supply's power to both dimmers so on your units with both channels dead you only have to buy one cube. That might be the place to start replacing bang for your buck wise.

I would also get an ETC tech in there to take a look at the rack. I have only seen a handful of sensor power cubes fail. 20+ means there is something much bigger wrong. Either you guys got a bad batch of dimmers, you have odd power, or your rack is overheating.

 

[ajb]

Thats the weird thing. I witnessed one die, it was powering house only 1000 watts were on that chan and then it started to ghost and then just died and it doesn't work any more.

It may have finally kicked the bucket then, but it could have been mortally wounded much earlier--by a hard short, for instance.

How old are your dimmers and how often do you pop the breakers? Have you kept the filters, racks, and modules clean?

 

[firewater88]

Sensor power cubes are about a hundred dollars each, give or take if you shop around. One power cube supply's power to both dimmers so on your units with both channels dead you only have to buy one cube. That might be the place to start replacing bang for your buck wise.

I would also get an ETC tech in there to take a look at the rack. I have only seen a handful of sensor power cubes fail. 20+ means there is something much bigger wrong. Either you guys got a bad batch of dimmers, you have odd power, or your rack is overheating.

My dimmers are about 7 years old now, and about 2 years into the new system, I was experiencing some issues and it turned out I had a bad batch of cubes. ETC sent me about 100 or so and I had to replace them myself and send the old ones back. I would contact ETC and check the code number on the pack.

 

[starksk]

Sensor power cubes are about a hundred dollars each, give or take if you shop around. One power cube supply's power to both dimmers so on your units with both channels dead you only have to buy one cube. That might be the place to start replacing bang for your buck wise.

I would also get an ETC tech in there to take a look at the rack. I have only seen a handful of sensor power cubes fail. 20+ means there is something much bigger wrong. Either you guys got a bad batch of dimmers, you have odd power, or your rack is overheating.

Kyle is correct in recommending having a technican look at the system.

I have a few additional questions for you in addition to the previously asked question of how old the system is:

Did this problem just appear or has it been growing over time?
Is there a circuit or circuits that seem to always have the issue come back even after you have swapped the module?

And seconding ajb's questions:

...how often do you pop the breakers? Have you kept the filters, racks, and modules clean?

If you haven't already, please also give us a call at 800-688-4116 and we can check date codes as well as give more site specific advice.

 

[Les]

Kyle is correct in recommending having a technican look at the system.

I have a few additional questions for you in addition to the previously asked question of how old the system is:

Did this problem just appear or has it been growing over time?
Is there a circuit or circuits that seem to always have the issue come back even after you have swapped the module?

And seconding ajb's questions:


If you haven't already, please also give us a call at 800-688-4116 and we can check date codes as well as give more site specific advice.

^ That's excellent customer service when they seek you out instead of the other way around!

 

[techno89]

I would say definitely call ETC and see if they will help you for low to no cost, cause something sounds really, really wrong.

 

[Silic]

The dimmers mfg date is 12/96 i don't remember when they were installed. we rarely pop them that I know of this is a high school theater so who knows as far as keeping them clean there little dust on them. I go in every month with a 1 gal shop vac and use it to blow out the dust. I've haven't ever seen a over heat message and the room never gets above 80 and is vented constantly. it been slowly growing in the last 5 years its starting to speed up lately. And doesn't seem to target any specific channel they just go at random. I've called ETC. Tech support told us to buy new power cubes which we can't afford. But they probably didn't have the authority to replace them. Also these are the Q141 power cubes

 

[JD]

Age should not matter too much. I have some 35 year old EDI racks that never lost a channel. (Although they have not been turned on in 10 years)

HOWEVER:

Age does become a factor if they have been running hot due to blocked or restricted ventilation. The heat may not have been high enough to trip an overheat protector, but the continual thermal stress on the power devices potted in the cubes (back-to-back SCRs) will cause stress fractures at the junctions. These are more likely to manifest themselves as "channel out" as compared to "always on" which occurs on a hard blowout.

Power cubes dissipate about 1 watt of heat for every amp of power flowing through them. ( 20 amps = 20 watts of heat ) Doesn't sound like much, but if the air is not flowing properly... Well, think how hot a 20 watt soldering iron gets!

The second thing that can cause this is a lightning hit / high surge. This can manifest itself through micro blow-overs in the junction. They may continue to work for a long time after the damage was done, but then start failing in mass.

Try changing a few out. I suspect the new cubes will not fail.

 

[jmabray]

It's also possible that Tech support didn't have the full picture. If you call tech support and tell them that you have a few dimmers out, that's going to be the standard response - well replace the power cubes.

However, if you tell them that, hey, I seem to have an inordinate number of power cubes out on a smaller system that is only 5 years old, then that's a different story.

If the dimmers were made in 1996 though, then my guess is that it's just age. They are almost 15 years old at this point. Dimmer racks do have a finite life span. I know that budget is an issue here, but I would approach the school from the standpoint of this spending should come out of the maintence budget, not the theatre budget. This is something that can go bad after a while - it's equivalent to a light bulb going out - they have a finite life span as well. I would approach it as something that needs to be done over the course of a few years. Do 10 a year for a thousand bucks a year, and you are back up and running. Easier for everyone to take from a financial end.