This is topic highest hours for a xenon bulb in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Chad Souder (Member # 343) on 02-12-2000, 11:45 PM:
Just wondering what the average bulb life should be for a xenon bulb. Also, I was curious as to records people had for most hours put on one bulb before it was removed.------------------
"All right, brain. You don't like me and I don't like you, but let's just do this and I can get back to killing you with beer." - Homer Simpson
Posted by Aaron Mehocic (Member # 15) on 02-13-2000, 12:20 AM:
Average bulb life depends upon the wattage of the bulb itself. Most 2000 watt bulbs average about 2000 hours before removal is required. 3000 watt bulbs are rated at a little less by their manufacturers, but will perform well past 2000 hours. I once put over 5000 hours on a Christie CXL-20r, religiously rotating it every thousand hours or so. The bulb was still bright and crisp at removal, but with 5000 hours your just asking for trouble. I don't recommend anyone running a bulb this long.
Posted by Ian Price (Member # 14) on 02-13-2000, 12:47 AM:
We had a 2,000 watt Osram in a Strong lamphouse, in one of our small auditoiums at the UA Greenwood, that we sort of forgot about. The lamp kept working. When we finaly changed it out, it had close to 6,000 hours on it and was completely black.When I broke it, it hardly made a sound.
Posted by Brad Miller (Member # 2) on 02-13-2000, 01:36 AM:
I ran a 2500 watt OSRAM in a Film-Systems lamphouse back in 1989 for 5600 hours. Bulb struck right up and still had good light (or at least what was considered good for those lamphouses). There was no darkening or spot of any kind on the bulb envelope. Generally we couldn't get much more than 2500 hours from that combination.The only other great performances of xenon lamps I've encountered is Christie lamps in Christie SLC consoles. That is one hell of a combination for excellent light and longevity of the xenon. I was visiting Joe Redifer's theater last week and saw he had a 2000 watt lamp at 6000 hours on a pretty big screen with fantastic light, easily 16 footlamberts! This is not that uncommon of a thing either. Put any other make of xenon in a Christie or put a Christie in any other make of lamphouse and all works nicely...but not like the complete Christie package does. 
Posted by Stefan Scholz (Member # 147) on 02-13-2000, 11:10 AM:
Any technical item has a mean time to failiure. According to math statistics, about 37% of all items reach their rated life without a major repair.
For bulbs, this would mean, a total failiure. So design life must be substantially higher than the warranted 2k hours at 22 min changeover operation.
This is, together with improved mfg. standards, why most bulbs could be run much longer.
Another factor of life is the No. of strikings, the AC ripple of the rectifiers, startup inrush current limiting, striking unit priciple (single puls igniters give less stress), cooling and ventilation, etc..
The 2k hours must be reached under any circumstances, with worst case operating conditions (all equipment specs at max allowable limits). So 5k hours at acceptable performance could be possible, and if the bulb reached that life, why not treat it even longer?
Posted by Aaron Sisemore (Member # 145) on 02-13-2000, 06:06 PM:
I changed an ORC 2000w bulb from Sebastopol Cinemas #5 due to complaints of a 'flickering picture'. The bulb had 7500+(!) hours on it upon removal, and was still striking on the first couple hits and running nicely, albeit a bit flickery, at 80A... I am sure this is the exception to the rule, as most other ORC bulbs dont get very far after the 2000 hour warranty period expires...Aaron
Posted by Joe Redifer (Member # 3) on 02-13-2000, 07:43 PM:
Brad-That 2000 watt Christie lamp has about 6200 hours on it now, doesn't have any noticable flicker, AND is playing with a flat movie on a 35 foot screen! The only bad thing is that sometimes it takes 4 or 5 tries to strike. Maybe that's the secret! Strike your bulbs as many times as possible for no reason (kidding).
Posted by Steve Guttag (Member # 268) on 02-13-2000, 08:00 PM:
For me it was a Christie CXL-30 for 15,000 hours....the tips looked SCARY but it still worked and it wasn't darkened...It was in a CK-30 console.
My best lamp lifes are generally Christie lamps and Christie powered.
Steve
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"Old projectionists never die, they just changeover!"
Posted by David Johnson (Member # 173) on 02-15-2000, 02:55 AM:
The longest bulb life we ever recorded was 35.000 hrs in Brisbane using a Kinoton 1.5KW lamp in an Fp30, hours around the 10.000 to 15.000 are normal in this lamphouse using Ushio bulbs.
David
Posted by David Kilderry (Member # 142) on 02-15-2000, 03:44 AM:
Ushio in the right environment - Kinoton or Cinemeccanica lamphouses - do last a long time. We had a 2,000w do 9,000hrs and still producing good, flicker free light on a 25 ft screen.We regularly achieve 3,000 hrs on 4,000w lamps with 16 footlamberts in centre of screen, Ushio again.
Posted by Steve Guttag (Member # 268) on 02-15-2000, 10:10 PM:
Ushio (aka Christie) lamps are extremely good lamps for conventional theatre products (I hear their IMAX 15KW lamps are wanting).Don't discount the Christie power supplies...they are rather clean power as compared to most other power supplies on the market.
The one I don't get is IREM...they have this good reputation but they put out some of the worst power. They even sell a very expensive filter kit to fix their poor power (an admission of guilt, if you ask me).
Ushio lamps and Christie power...a very good combination, regardless of lamphouse
Steve
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"Old projectionists never die, they just changeover!"