This is topic Lamphouse 'Popping' in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Mathew Molloy (Member # 666) on 09-17-2002, 03:41 AM:
Tonight my friend's ORC(900?)with the self-contained rectifier 'popped' when it tried to strike the lamp and there was a flash. He tried it three times and it always made this loud, electical pop with a flash but the lamp did not light. I told him I'd ask you guys what you think it might be. When I got home I heard that he tried it again after I left and it struck just fine. Any thoughts?Also he was thinking about removing the bulb and seeing if the pop was there without the bulb. I didn't think that was a good idea. Is it bad to power up a lamphouse with no bulb?
Posted by Paul G. Thompson (Member # 655) on 09-17-2002, 04:36 AM:
Mathew, It sounds like the anode lead is too close to the metal mirror. It could also be fouling on the hand douser blade. DON'T remove the bulb and fire the igniter!!! It could do damage to the igniter and also destroy the control boards.
Posted by Mathew Molloy (Member # 666) on 09-17-2002, 05:24 AM:
Thanks Paul! When he asked me if he should fire up the lamphouse without the bulb I realized that neither in my six years of union work nor any time before or after that had anyone said anything in regards to NOT doing that. It just seemed wrong and I remembered my 16mm Xenon had a sticker saying "do not operate without lamp in place".
Posted by John Pytlak (Member # 331) on 09-17-2002, 07:38 AM:
I think Paul "nailed it". The anode lead is arcing to something, most likely the douser or reflector.------------------
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Posted by Don Sneed (Member # 955) on 09-17-2002, 08:21 AM:
Mat, I think Paul & John nailed it alright, even if the anode lead is not touching the dowser or reflector, if it is close to these the high voltage will arc or jump from this lead to the metal, be sure to move the anode cable lead away from these & try the lamp again, most of the time the arcing will rob the bulb from striking, just move the cable away from the reflector or any metal it is near to...good luck !!
Posted by Barry Hans (Member # 477) on 09-17-2002, 08:44 AM:
Same thing happened to me. Just like what everyone has said, it was the anode lead arcing to the housing.
Posted by Wes Hughes (Member # 981) on 09-17-2002, 03:35 PM:
The cathode lead will do it too. Happened a couple of times on a few of my Xenex II lamphouses when the lead was too close to the back side of the mirror.
Posted by Dave Williams (Member # 299) on 09-19-2002, 01:41 AM:
I have had that same problem before, and Paul did in fact nail it right on the head. Get a technician out there pronto!Dave
Posted by Pete Naples (Member # 761) on 09-19-2002, 02:54 AM:
The anode lead on the baby Orcon is notorious for this. Also watch out for it having frayed, often a sliver of wire will be poking out and is arcing on the douser.
Posted by Tony Ratcliff (Member # 1196) on 09-23-2002, 01:23 PM:
I have an ORC as well. This has happened to me a couple times after changing the bulb - I have the lead too close to the case.
Posted by Mathew Molloy (Member # 666) on 09-23-2002, 05:28 PM:
Thanks guys! You hit the nail on the head!