Film-Tech Forum ARCHIVE: ORC 1000 lamphouse repair?

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Posted by Ed Inman (Member # 2583) on 11-28-2017, 06:43 PM:

One of my ORC 1000 integrated lamphouses won't light. When you switch on the current it sparks--i.e. sparks exit from the top of the fan. Does anyone have the experience to still repair these? (I know a lot of people loathe these things so I don't need reminding of that--LOL--just would like to get it working without breaking the bank if at all possible). Thanks.

Posted by Steve Kraus (Member # 476) on 11-28-2017, 11:23 PM:

Sparks actually come out the fan vent or are you just seeing the bulb flash from the igniter zapping it? We should get that cleared up right away.

Posted by Ed Inman (Member # 2583) on 11-29-2017, 10:30 AM:

Yes, actual sparks coming out of the top fan vent every couple of seconds when the igniter tries to start the lamp. If you know of anyone in Chicago who can work on these I'd love to link up. Thanks.

Posted by Mark Gulbrandsen (Member # 72) on 11-29-2017, 11:52 AM:

Take the top off disconnect that fan and stand behind the lamp house and light the lamp. See where the sparks are coming from. But keep at an angle where the reflector covers the bulb gap so you don't burn your retina. It might be an easy fix and it might not be... Some times they can arc to the front douser and then sparking from the igniter occurs.

Mark

Posted by Ed Inman (Member # 2583) on 11-29-2017, 04:09 PM:

I think the sparks are coming from the igniter. I'm better with mechanics than electronics and the thing has always made me a little paranoid as far as tinkering around with it. But I will give your suggestion a try, and look for any obvious shorts or other problems. I know the cable to the front of the lamp was replaced recently by someone I don't really have 100 percent confidence in. Who knows--maybe something is just loose. It may take me a few days to get around to it but I'll try to post a link to a video to show what's going on. Thanks for the suggestion. Any help or advice is appreciated.

Posted by Louis Bornwasser (Member # 3063) on 12-02-2017, 08:35 PM:

See if that cable is too close to any metal edge, say, the edge of the reflector or the douser door.

Posted by Dave Macaulay (Member # 813) on 12-03-2017, 06:10 AM:

Sparks flash between two points so I don't think they are flying through the fan into thin air.
Since it's trying to ignite, the lamp DC power supply is probably OK and giving its "lamp off" open circuit voltage that triggers the HV ignitor.
This is a pretty high voltage (thousands of volts) above ground which will arc to somewhere grounded. It should arc inside the lamp and ionize the gas between the electrodes, allowing the DC lamp power to cross the gap. But it will be quite happy to arc to anything else,
Since a cable was replaced "by someone I don't really have 100 percent confidence in" possibly that cable has inadequate insulation - the original cable had rather thick insulation - or was routed improperly. If it touches any metal with a sharp edge the insulation can break down and allow arcing, that carbonizes the plastic which becomes a nice conductor and the arcing gets worse.
Remove the cover and defeat any safety switches (not sure if the 1000 has any?) and see where the arcing is. Be very careful and stay back, that HV pulse is very dangerous and even the lamp power supply DC open circuit voltage is enough to kill you.
If it is actually flashing inside the lamp then replace the lamp.
Maybe a rerouting of the cable will fix it, possibly you can add a sleeve over the wire (multiple layers of electrical tape, or silicon tube is good) where it's arcing.

Posted by Ed Inman (Member # 2583) on 12-03-2017, 03:20 PM:

Hey guys: Success! I think Mark was onto something. I observed that the lamp appeared to be extended out too much to the front (compared to my other unit) and so I think it was arcing to the douser and shorting out. When I removed the lamp I observed someone had put two rings on the rear screw-in threads. I removed one and was able to screw back the lamp another half inch or so. Now it appears to light properly. Knock on wood. Thanks for all your suggestions. Very much appreciated. --Ed