Film-Tech Forum ARCHIVE: Lamphouse stopped working then started again, Why?

This is topic Lamphouse stopped working then started again, Why? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Jason Thode (Member # 1854) on 03-17-2004, 12:23 AM:

The lamphouse in question is a Strong Highlight 2 brand new out of the box barely has 200 hours on it. The bulb in it would not strike, at first we thought it was the igniter and so changed it out with another house of the same wattage. That house proved the igniter was faulty because it too would not strike. After calling it dead we put it back together and called in for a spare to replace it. The next day a projectionist turned on the projector and struck the lamp like it had no problem. The lamp fired right up with no problems. Can anyone tell me what happened and why?

Posted by Bruce McGee (Member # 131) on 03-17-2004, 09:24 AM:

Possible defective lamp?

Posted by Gordon McLeod (Member # 33) on 03-17-2004, 09:47 AM:

Obviously it wasn't the ignitor and the trouble shooting methodology seems then at fault
Air floor and door switchs are often the culprit for a lamp not lighting on the Strong consoles
two impoints that should have been checked and reported in the post
Did the rectifier actually switch on or attempt to switch on
If so what did the meter show as the no load voltage

Posted by Rick Long (Member # 213) on 03-17-2004, 09:53 AM:

What size bulb are you using? Strong has suggested a modification for ignitors used on 6 and 7 K bulbs where hard-starting is an issue.

Posted by Paul G. Thompson (Member # 655) on 03-17-2004, 10:58 AM:

If you could not hear the contactor close in the power supply and the bulb made no attempt to autostrike, I think it is time do dismantle the internal blower and clean the tumbler. Also make sure the air flow switch is opertating smoothly. Check the rest of the interlock circuit, too.

A partially plugged internal blower can also raise Cain with bulb life even if you have a booster blower attached. It is amazing how many people accidently forget to keep it clean.

Posted by Joshua Lott (Member # 240) on 03-17-2004, 12:12 PM:

It could be the ignitor. I once had a similar problem w/ a strong lamphouse. All you had to do to make the ignitor work was tap on the ignitor.

It was very strange and we ended up changing out a piece in each ignitor for all of our projectors with that size lamp.

Posted by Mike Babb (Member # 1379) on 03-17-2004, 06:49 PM:

I had a similar problem and it had to do with the connectors on the back of the control panel. They hadn't been crimped into the connectors well and weren't making good contact. With the manual switch on, if you opened the back door and wiggled the wiring into the connector it would strike.

Posted by Chris Hipp (Member # 1788) on 03-17-2004, 06:55 PM:

Poor Jason, I guess you miss your christie lamphouses now?

Is this analog or digital display card? The digital card are known for being very screwy. I would bet that it is in the interlock system and nothing to do with the bulb or igniter.

Posted by Rick Long (Member # 213) on 03-17-2004, 08:58 PM:

The first question is to decide if the problem lies with bulb, ignitor OR control circuitry;

Are you getting four green lights on the switch panel with the lamp switch set to the ON position?

If so, the control circuitry would SEEM to be doing its job, so it would appear that the ignitor MAY be the problem.
You already changed the bulb and didn't accidentally break the thin nichrome discharge wire that runs around the glass bulge of the bulb, did you?)

If the ON green light is lit check the rectifier output voltage. Push the momentary VOLT side of the ammeter switch.
Look for +100 volts - pre-strike, dropping lower if the xenon bulb ignites.
If these conditions are met, and the lamp is still not igniting, try the suggested Strong ignitor modifications.

If the ON green light is not coming on, the problem is likely with the control circuitry. (Check door switches, wind vane at the top of the lamp in the exhaust stack), or poor wiring connections at the switch panel harness.
Note that if it is a switching rectifier, you may not hear it turn on (solid-state switching control - no contactor).

Posted by Jason Thode (Member # 1854) on 03-18-2004, 03:30 PM:

Chris the card is analog and we had four lights, indicating the doors were closed. The bulb was also inspected and seemed fine, as a precaution though we changed out the bulb and put a new one in. As for any noise from the inside if the bulb was actually trying to strike nothing, no sound, not even a hum. [Eek!]

And Chris, YES I DO MISS MY OLD CHRISTIE LAMPHOUSES!! [thumbsup]

Posted by Chris Hipp (Member # 1788) on 03-18-2004, 03:56 PM:

Consider yourself lucky, the digital cards are horrible. I do have a lamohouse that tends to not strike every once in a while and makes no sound at all then you try to strike it again in a few minutes and it will be fine.