This is topic Igniter Arcing problem in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Chris Hipp (Member # 1788) on 07-30-2003, 03:04 AM:
I have a problem with one of my lamphouses, any igniter that I install arcs to the base of the lamphouse. It is a highlight II lamphouse with a switching power supply.
The engineer cut some things off from the inside of the igniter, I'm not sure exactly what as I don't know much about electronics, and the bulb strikes and stays lit fairly well but it cuts out int he middle of the show for a few seconds sometimes.
Anyway, my question is what would cause the arcing? It's very nerve wrecking to have the bulb turn on and off in the middle of a show.
Also, I'm curious if anyone else is having problems with the quick disconnect wiring harnesses burning up, I've had three go out in the past 2 months and one last year. The lamphouses were all around 17,000 hours.
Thanks
Posted by John Pytlak (Member # 331) on 07-30-2003, 07:25 AM:
The deteriorating wiring harness may indicate a heat/venting problem. Likewise, the lamp cutting out mid show may show you don't have sufficient draft, and the air flow failsafe switch may be shutting down the lamp when the air flow is not sufficient.
Posted by Greg Pauley (Member # 503) on 07-30-2003, 12:08 PM:
“Anyway, my question is what would cause the arcing? It's very nerve wrecking to have the bulb turn on and off in the middle of a show."
Like John said, check your air flow switch in the lamphouse and make sure it's not loaded with dirt and that it’s functioning properly. Also, is your switcher power supply getting enough air flow? This would cause the bulb to shut down until it had cooled down to restart.
Posted by Chris Hipp (Member # 1788) on 07-30-2003, 01:43 PM:
It can't be the air flow sail switch because the digital diplay card also went out so the safety switches are all bypassed. That is another problem we are having, occasionally when a power supply goes out the display card and the PCB board go out and even after replacing them it gives fasle readings and says that doors are open that aren't and so forth.
As far as the power supply, the fans are working inside and the vents are not clogged up with dirt or anything. I don't have any extra cooling on it though.
I think you are right about the wiring harnesses, a lot of our blower fans had not been cleaned in a long time. I went through and cleaned them all when I took over. Of The houses that have burnt up, three are running 6k bulbs and the oher was running a 4k.
Posted by Gordon McLeod (Member # 33) on 07-30-2003, 05:49 PM:
Often the UV light in the console attacks the wireing harnesses and makes the insolation fall off
Posted by Scott Manley (Member # 867) on 07-30-2003, 09:15 PM:
I once had a Highlight II (7K)that had a digital display blow a couple switchers and the digital display board....It didn't have the quick disconnects but a problem I found there was was bad connection on the connector that goes to the pot for current adjustment....They said that the bulb current would go high then everything blow.
Don't know if this helps....but my two cents are in.
Posted by Rick Long (Member # 213) on 07-30-2003, 09:23 PM:
It appears you have two seperate problems, the arc going out in the middle of the show (which I think may have been solved by some of the members here), and the arcing which results when the lamp is started or re-starts itself after a failure.
It is important to know exactly where this arcing is occurring; from the ignitor to frame or (as happened to me recently), from the teflon bulb adapter to ground? In my case, the cure was replacement of the adaptor.
The two things the engineer cut off the underside of the ignitor circuit board were capacitors. This proceedure was recommended in a memo by Strong to be used in cases of hard-starting with 6K bulbs.
Posted by Dave Macaulay (Member # 813) on 07-31-2003, 08:43 AM:
The ignitor will not arc and cause the lamp to go out. It doesn't really do anything after the lamp is on and the 25VDC or so in the running lamp circuit isn't going to arc much anywhere unless something shorts out, in which case you won't have any problem seeing where the short occurred because there's going to be stuff melted.
I wonder what you mean by arcing to the base of the lamphouse? There's a wire connected to the positive lead feedthru from the ignitor, do you see some arc tracking there?
With the digital display board, you have lots of things that can go wrong. Make sure that board is 100% OK. All the safety circuits attach to it and it controls the rectifier. These boards routinely get fried if a lamp explodes...
The wires connecting at the back of the lamp (bottom rear inside the inner lamp box) do suffer from UV decay, I've seen them with no apparent insulation but the lamphouse still running with no problem - maybe you're not so lucky? Since these wires go to the digital board there may be an issue.
Sounds like either a rectifier of digital board problem here. Of course it could well be a door or airflow switch going funny. If the lamp strikes reasonably quickly when asked, don't look at the ignitor for problems when the lamps goes out.
And be careful if you open up a DC ignitor! That @!*%$# circuit board holds a really surprising high voltage charge for a long time... not deadly perhaps but not pleasant.
Posted by Chris Hipp (Member # 1788) on 07-31-2003, 12:03 PM:
It is arcing from the bottom of the igniter to the platform in the lamp house, if that makes more sense.
Posted by System Notices (Member # 2357) on 12-19-2011, 04:21 PM:
It has been 3063 days since the last post.
Posted by Dominic Espinosa (Member # 2122) on 12-19-2011, 04:21 PM:
Did you ever find out/do you remember what caused the arcing from the ignitor to the housing floor?
I have a house doing the same thing.
Last time the lamp refusd to strike it was arcing in the rear bulb support. This time its right out the bottom of the ignitor where the 2 leads drop out.
Posted by Robert D Hall (Member # 5674) on 12-19-2011, 07:49 PM:
I have had a number of ignitors do that over the years. And was told by Strong it was most likly a bad capacitor but they were not field serviceable. So i would just ship thim in for a repair exchange.
BY the way i wouldnt recommend opening one up. As some one all ready pointed out they hold one hell of a charge. I opened one up to look around inside that had not been in a unit in over a month. I see a flash the next thing i know is im on the floor i didnt know how i got there.
Posted by Dominic Espinosa (Member # 2122) on 12-20-2011, 05:59 PM:
Well this is a new one on me.
The bulb, despite being relatively new seemed to be the culprit this time.
Odd.
Posted by Richard May (Member # 2627) on 12-21-2011, 07:45 AM:
I don't think it's THAT odd. With the lack of quality control with xenons the last few years, I'm not surprised. I have had more than a few give out with few hours on them. Also, it has not been just one brand.
Posted by Burleigh Ibbott (Member # 3917) on 12-21-2011, 10:45 AM:
Not sure if this would help but i have had the main switch for the projector and rectifier play up. The same thing happened to me during a performance, it stopped then started again up again which in turn I had to start the lamp up again.
May be something completely different but sometimes it can be as simple as that.
Burleigh