Film-Tech Forum ARCHIVE: Xebex Lamphouses

This is topic Xebex Lamphouses in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Chris Byrne (Member # 1563) on 03-11-2003, 10:02 PM:

Is there anyone else on this site who uses Xebex IIIR Lamphouses?

The reason I ask, is that I was informed yesterday by my engineer that these lamphouses are slightly inferior and not designed to get quality hours out of a bulb.

I run ushio 3000HK-O bulbs and average 4000 - 5000 hours out of them. I have reached as high as 8000, however not since I commenced pumping them up to 100A for better light. I know the bulb is rated at 110A, however my rectifiers (USHIO KCX 100U4) are only rated at 100A.

While I have no doubt that the advice passed on is true, I would be keen to hear what other techs have to say.

Also on the topic, looking back through our booth logs; dating back 13 years, there had been bulbs getting up to 13000 hours. I know for a fact that the Tech before me never used to run bulbs above 90A (which is supposedly not good for the bulb) and would rotate them every 1000 hours. Why the big deviance if there is no obvious reason for this?

Posted by Darryl Spicer (Member # 711) on 03-11-2003, 10:19 PM:

hmmmmmmmm that's a lot of hours. You have bomb squad insurance or something. most I ever saw a lamp get in hours was 4000 and it exploded in the lamphouse. It was in a strong super lumex 2 lamphouse. I will stick to since I have to anyways changing out at 2000hrs. It's past warrenty and if it blows and takes out the mirror or damages the reflector bowl no coverage by the lamp manufacturer. You have to understand these are CFS lamphouses that I use and they do not like to run the bulb after 2000 hors without flicker or hard starts.

oh wait a minute I see you have the bulb change safety equipment on in your photo. I guess you have to wear that all the time. [Smile]

Posted by Daryl C. W. O'Shea (Member # 1303) on 03-11-2003, 10:27 PM:

Running bulbs for that long, a lamphouse that is particularily hard on bulbs is the least of your worries.

You're not going to have good light on the screen after 8000 hours. Even 4000 hours is pushing it.

Posted by Richard Fowler (Member # 893) on 03-12-2003, 08:19 AM:

The Xebex lamphouse series was designed many years ago and some new reflector designs have been developed since then which are not incorporated by this equipment. The Xebex is part of the Ushio family of products and overall is a decent unit. I have seen many on my travels out of the USA. They where available in some markets in a disassembled, knocked down kit for easier customs entry and shipment.
Richard Fowler
Kinoton America Inc.
Know your product.....and all of your competitors [Wink]

Posted by Dave Macaulay (Member # 813) on 03-12-2003, 09:40 PM:

That's a pretty good lamphouse, I've never heard it called hard on lamps. It isn't easy to get parts for them but reflectors are available.
The lamp adjustment system is brilliant though. If you're used to it and go to a Strong you'll be crying.
The blower needs attention in the clean-and-oil department or the lamp will be undercooled, keep an eye on it though and you should get fine lamp life... and if the fan seizes the transformer tends to fail as well. Obviously 4000+ hours is great if you actually get good light out of it then! I expect the envelope will have darkened a lot and degraded the light considerably though.

Posted by Gordon McLeod (Member # 33) on 03-13-2003, 09:20 AM:

In the great white north the Xebex was for a long time one of the most commonly installed lamphouses with the Sanrex rectifier
Never had any issues with poor lamp life but cooling is an issue. The exhasut must be up to snuff
Also those rectifiers can have very dirty DC in standbye mode and it is a good idea to get the filter caps checked as a lot of them start to dryout

Posted by Chris Byrne (Member # 1563) on 03-14-2003, 08:00 PM:

With all due respect, if I pulled bulbs regularly at 2000 hours, I would get a 'Please Explain' note on my desk.

I agree that when the bulb reaches about 4000 hours, the light starts to drop off dramatically and it's time to weigh up the pros and cons of changing it soon after.

As we don't run in stand-by mode, I can't compare the advantages of such, however the blowers and exhausts are maintained efficiently.

What were you having a go Darryl, that is my uniform! [Big Grin]

Posted by Bill Carter (Member # 156) on 03-14-2003, 08:16 PM:

When I first took over my theater, there were a couple of Osram bulbs with more than 7000 hours on 'em in the Super Lumexes. They would still strike up, but that's about all I can say for them. I actually saved one of them for a while, because it was absolutely the blackest thing I've ever seen.

Posted by John Pytlak (Member # 331) on 03-14-2003, 09:27 PM:

With age, the quartz envelope blackens, and absorbs more energy, so it gets even hotter. With age and heat, the quartz vitrifies and the seals weaken, making catastrophic failure more likely.

As the electrodes erode, ignition often becomes problematic.

And as the lamp ages, light output decreases. If you can't maintain at least the 12 footlambert minimum specified by standard SMPTE 196M, you are cheating your audience.