Film-Tech Forum ARCHIVE: Xenon Bulb Staying On

This is topic Xenon Bulb Staying On in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by John Cruz (Member # 6531) on 12-09-2011, 04:14 PM:

I could really use some help trying to figure this out. We have an Orcon CV2000 lamphouse and automation panel that goes with it. For the past week or so the xenon bulb has not been turning off after each show. The cue reader is working fine (and we did not leave the xenon bulb switch ON [Big Grin]

. A few times this week the motor also stayed on after our outboard cue went through the cue reader. The shutter closes, but the light stays on after every show, and as I just mentioned, the motor stays on some times as well.

I thought it might be one of the relays in the automation panel so I tried to swap out the motor and bulb relays but the problem persists.

Any advice on what to try next or how to fix this would be greatly appreciated. We have gotten around the problem by turning off the master power to the lamph house after each show, and then turning it back on before the following show is scheduled to start. (Just to clarify, the bulb only stays on after the show is over. Once I switch off the power to the lamp house and turn it back on, the xenon bulb stays off).

THANKS!

Posted by Richard May (Member # 2627) on 12-09-2011, 04:28 PM:

What automation do you have? Sounds like maybe the hold relay.

Posted by Justin Hamaker (Member # 2165) on 12-09-2011, 04:29 PM:

I had a similar problem on one of my Century projectors.

We used the Neumade cue detector. While the cues would trigger the automation events such as dimming the lights and closing the shutter, the projector shutdown resulted from the tail of the film dropping out of the cue detector after the end of show cue had been read.

Occasionally the projector/lamp would fail to shut down after the film dropped out. To the best of my understanding, the issue was related to the switch which was connected to the rollers that dropped when the film dropped out. The problem happened so infrequently (maybe once a month) that it was difficult to trace the actual source, but I do believe it was that switch and not the cue detector.

Posted by Monte L Fullmer (Member # 2797) on 12-09-2011, 04:45 PM:

What brand of failsafe is attached to the projector?

If it's a dry contact, microswitch type, it's not opening when the roller legs drop causing your system to remain on - being the motor and lamphouse..

..seen that many times when a microswitch fails out on older roller contact type failsafes.

Another one: if the microswitch is good, then we have to look at the "STOP" relay (one of those small "icecube" relays) in the automation to see if it's getting power, plugged in and not loose, et.al., and the easy way to test is to lift an drop the roller legs and see if that relay opens and closes-that will show that the microswitch is working.

Also, when you hit the "STOP" button on the automation, does the lamp and motor then shut off? If so, then the microswitch is likely to be at fault in the failsafe.

Posted by Gordon McLeod (Member # 33) on 12-10-2011, 11:07 AM:

What particular make of automation is it and cue detector
It could be the manual switchs on the auto that are shorted
Also If it is a Raven or HiTech the control to the relays sometime doesnt unlatch

Posted by Richard Hamilton (Member # 321) on 12-13-2011, 08:54 AM:

Gord,
Don't badmouth Hi-Tech [Razz]

. While I only had the privelage of working on a couple Hi-Tech automations in the field, I was good friends with Lisa who built and repaired them. When we shut down Megasystems, Lisa still supported the Hi-Tech stuff, working out of her garage.

I heard the Hi-tech Automations were crap (low cost, but gets the functions done). For the large format stuff, which is what I did there, we used a PLC based automation.

Rick,
partial owner of Hi-Tech, if I ever find the stocks [Confused]

, I think the ex stole them in the divorce [fu]