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Author Topic: Defective lamp(s) or lamphouse issue? Galen Murphy-Fahlgren Master Film Handler Posts: 405 From: Canton, MI, USA Registered: Oct 2007 posted 07-20-2008 06:23 PM                     First, technical info: Big Sky C-series console, set up for 4000-6000 watt lamps (from what I'm told) Currently running a 4200w LTI Helios lamp after our immense dissatisfaction with the 5000w Osram XBOs (reliability, output, lifetime). My story involves replacing our first Helios lamp with our second and third Helios lamps, for frame of reference. Last week, one of my booth ushers and I were replacing the xenon in my largest theater in preparation for Dark Knight (plus, due to my company's excellent purchase order system, it was way over hours), this being his first experience changing a xenon. Since he hadn't done it before, I did all the lamp handling, explaining to him what I was doing as I went. I then had him make the adjustments so he could see how an adjustment either way affected the light on screen. Anyways, the front end of the lamp ended up coming halfway off of the pedestal it rests on, so I shut it down so I could fix it once it cooled down. Once I put it back on, I started it back up and started re-centering the adjustments, but was having trouble because my guy had somehow gotten it pretty misaligned. Right then, I noticed wispy smoke emitting from the snood area, and shut everything down immediately. I called the assistant manager up and she and I decided to stick in the other new lamp we had just gotten in. At this point, we're coming up on show time, but we managed to get it in and focused well quite quickly, and were very happy with this xenon. Fast forward to this weekend, this lamp is striking hard, to the point that we have to use the manual ignition at times. At startup, it reads very low wattage compared to the previous lamp and its rated output. About 20 minutes in, the wattage is at spec, and both amperage and voltage are consistent with my logs of the previous lamp, although it had reached those figures almost immediately after startup and been quite consistent through the show. Back to the "smoking" lamp, I inspected it very closely today and found no visible signs of burning, scorching, discoloration, or any other defect I can imagine, and I suspect the smoking was coming from the lamphouse as a result of the poor alignment of the xenon/reflector. I also can't think of anything on/in a xenon that would emit smoke. My information of the time when we used the Osram XBOs is secondhand from the GM and from paperwork, since I started training in booth in August and didn't get a level of involvement in serious maintenance until October/November (again, I work for one of those "booth usher" chains). I do have the history for that lamphouse that shows that, in addition to being generally lax about changing xenons on time, my predecessors replaced three 5000w Osrams within 100 hours in the last 3 1/2 years since that auditorium was built. Any insight would be appreciated, and I can certainly get more technical info if needed. Being relatively inexperienced and having no real background in electrical systems, I don't really know what info is useful. Thanks in advance.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-20-2008 09:20 PM                     Did you examine the interior of the lamphouse after the "smoke" when changing the lamp again probably when the focus was adjusted you shifted the hot spot onto the snood interior and burned off the paint Do a close physical examination What type of rectifier is used with the lamphouse  |  IP: Logged Galen Murphy-Fahlgren Master Film Handler Posts: 405 From: Canton, MI, USA Registered: Oct 2007 posted 07-20-2008 09:34 PM                     I did not inspect the interior of the lamphouse because of the impending start. In fact, it didn't occur to me that it wasn't the lamp until later that day. The rectifier is an IREM, I believe, I am going in later tonight and can try to look up precise info.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 07-20-2008 09:45 PM                     Check for loose or charred connections in the recifier specificaly around the main contactor  |  IP: Logged Galen Murphy-Fahlgren Master Film Handler Posts: 405 From: Canton, MI, USA Registered: Oct 2007 posted 07-20-2008 09:57 PM                     Thanks, will do. The last show gets out just after midnight, and I'm heading in to have a go at it tonight. Hopefully we'll resolve the issue and save the area manager a trip down in the morning. He doesn't like mornings.  |  IP: Logged Tony Bandiera Jr Film God Posts: 3067 From: Moreland Idaho Registered: Apr 2004 posted 07-21-2008 02:59 PM                     Not familiar with your console, but in a Strong console had a similar problem once. You'll need to check very carefully (if your console has one): The pass-thru stud where the lamps' lead connects...from you description it sounds like the lead on the underside is loose, and making poor contact. Since you mentioned smoke coming from the lamphouse and now have hard strike and current issues this seems the most likely cause. If the connection is badly discolored you will need to replace the lead and the stud, cleaning it up will only work in the short term. I'm gonna look over in the manuals on here to see if your console is listed.. Edited to add: The C-series console is indeed here, but I couldn't find any pictures of the inside of the lamhouse in it, so I'm taking a guess at the design of your console with this reply..  |  IP: Logged Galen Murphy-Fahlgren Master Film Handler Posts: 405 From: Canton, MI, USA Registered: Oct 2007 posted 07-21-2008 04:03 PM                     Well, we put the "smoking" lamp back in and it works just fine. I did find a spot on the snood that appears to have lost some paint. It is a little dim, and I had to turn the amperage up slightly more than I like, but I'll have another go at focusing it. I'm still not ruling out issues with the lamphouse, just because of the frequency with which we have problems with it. It is the only one that takes higher wattage lamps, but I really doubt that there is that huge a gap in QC between the 4000w Osrams, with which we have never had problems, and both the 4200w LTIs and 5000w Osrams.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 07-22-2008 07:21 PM                     quote: Galen Murphy-Fahlgren this lamp is striking hard, to the point that we have to use the manual ignition at times Welcome to the gastly world of the LTi's - worst bulb that I ever worked with. Every LTI that we worked with - a good dozen of these 2000w POS's - NEVER lasted past warranty. In fact, I had flicker and hard strike halfway to warranty and replaced them back to Christies. I worked in a large complex where we had 6000w Christies and I manage to grab double life out of them - 900 hrs past warranty without any issues outside of the light begin to look a little dull and they would still strike on the first pulse. ..I'll stay with Christies - more bulb for the buck. -Monte  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 07-22-2008 09:21 PM                     quote: Monte L Fullmer ..I'll stay with Christies - more bulb for the buck. Ha! It took your company gurus a long time to learn that the hard way though . With proper cooling over 20K hours can easily be had from the 2K's. Mark  |  IP: Logged Galen Murphy-Fahlgren Master Film Handler Posts: 405 From: Canton, MI, USA Registered: Oct 2007 posted 07-23-2008 12:23 AM                     Our first LTI, the one that I removed a week ago, lasted about 140% of warranty without any flicker or dimming. That was with running the lamp at 4200w. I was more than satisfied by its performance, especially compared to the Osram that had been in there before, which started to dim severely at about 75% of warranty, and had to be changed by warranty. As far as I know, none of our theaters use the Christies, and since we are getting Barco DLPs, which don't take Christies, our company is not willing to inventory other brands for whatever reason.  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 07-23-2008 02:53 AM                     quote: Mark Gulbrandsen a long time to learn that the hard way though ... esp when I came on board to swing them in the right direction....(just felt bad in having them try LTI's..oh well..live and learn. The other fellow they had, I was wondering about him at times...) quote: Mark Gulbrandsen With proper cooling over 20K hours can easily be had from the 2K's. ..won't argue with that one - I pulled a 2k CHR out of our X-90 consoles with over 7800hrs. Envelope was still clear, good strike and light output, but just had a little flicker that started to become noticable due to the "ripple" horns on the anode lug growing on each side of the lug at a good rate. ...just hated to pull it out being that it still look good on the screen, but when I popped it for destruction, it just shattered with a very little pop.. Heard that the large wattage LTI's do keep the life in them. Just that these large bulbs are prob in more demand than the smaller ones, thus LTI is prob putting more QC with this demanded size (prob due to more sales than anything) than the smaller ones - why we had rotten luck with these bulbs. We tried LTI's for their light, in which I was fully satisfied with, just that the hours couldn't match the light for $value$ - and we depend more on hours and duration that spending the dough for bulbs that just meet full warranty hours, or even at full credit warranty like the other chains do - where light output and brilliance is more of a priority than duration . ..why we opted for Christies over Osrams and will not try any other bulb.  |  IP: Logged Bryan M. Montgomery Film Handler Posts: 47 From: Chillicothe, Ohio Registered: Jul 2007 posted 07-23-2008 12:11 PM                        Galen You have two problems, LTI bulbs and Big Sky consoles. I have 16 of the C-2000, series 1 and its a bitch and a half to get any good light out of them. I could go on and on about the poor design of these things. Mis-alligned access holes for bulb focusing "tools", lamphouse douser plates mounted with a single sheet metal screw that acted like a hinge, dropping the plate into the lightpath over time, etc. They suck. We have found that like a lot of equipment however, certain things work better in certain combinations, in this case, our Big Sky's seem to favor Osrams. If its possible, I would try to get some Osrams, those germans make a dandy bulb and they seem more compatible with the Big Skys'. Hope this helped.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 07-23-2008 06:54 PM                        I will defend the Big Skys; still my preferred lamphouse. There is noting wrong with them that a proper, professional alignment will not cure. (Remember Optiform makes nearly all of the reflectors now.) Louis  |  IP: Logged Bryan M. Montgomery Film Handler Posts: 47 From: Chillicothe, Ohio Registered: Jul 2007 posted 07-24-2008 11:42 AM                        I will say this, I believe I may have gotten some of the very first units they ever made, so its expected there will be some bugs in there.  |  IP: Logged

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