This is topic Lamp Ignition Problems in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Matt Ashburn (Member # 573) on 09-04-2000, 07:15 PM:
A theatre I'm working for is experiencing problems with a Lume-X Lamphouse. The lamphouse is powered by a Strong 61001-10 power supply, and it is using an Osram lamp. Over the past couple of weeks, they have reported that the bulb is taking longer to light (now takes upwards of 10 or more "strikes"). They say that the problem is increasing with time.
What can cause this? They fear that it will simply not strike one day.
Thanks in advance,
Matt Ashburn
Hollywood Cinema
Martinsville, VA
Posted by Randy Stankey (Member # 64) on 09-04-2000, 07:29 PM:
The first question I'd ask is how many hours are on the lamp? If it's getting old I'd try changing it.Second thing I'd do it check the amp and volt readings right at the moment of strike-up... If the voltage reading (press the "volts" button next to the amp meter) pegs the needle immediately upon power up then it's okay. At the moment the lamp lights it will drop to its normal reading... The amps reading is just the reverse. It should read next to nothing until the moment of ignition then it will immediately jump up to the normal reading. It may take a minute or two after the lamp lights for the readings to fully stabilize. After the lamp heats up to operating temperature the readings will settle down.
I wouldn't check other things until you've verified that your lamp is good.
Posted by Paul Konen (Member # 41) on 09-04-2000, 07:33 PM:
Probably getting way over on hours. The anode tip is probably wearing away and the arc is having a harder and harder time of jumping the gap.Replace the bulb !!
Posted by Matt Ashburn (Member # 573) on 09-04-2000, 07:50 PM:
The bulb isn't too old. The theatre has only been open for about 5 or 6 months. I'll call them and have them read the hours, if you think it's necessary.
Posted by Matt Ashburn (Member # 573) on 09-04-2000, 08:37 PM:
With the number of shows that are going, I estimate that the hours are around 1350. I'll check and get the actual numbers.<UPDATE: It appears taht the hours meter isn't operating on this lamphouse. Where can I get a replacement?>
Posted by Ken Layton (Member # 133) on 09-04-2000, 10:11 PM:
Contact your Strong dealer and order a new meter.
Posted by Pat Moore (Member # 380) on 09-04-2000, 10:13 PM:
This must be a used Super Lume-X System with that power supply model number, so who knows about the lamp? What is it's wattage? What current is it operating after it has stabilized? A 2kw lamp running at too low a current will bet hard to ignite, even if there aren't that many hours.The replacement hour meter is available thru your normal dealer.
Posted by Gordon McLeod (Member # 33) on 09-05-2000, 09:23 AM:
The Lumex lamphouse has aignitor that is a little strange
In the rectifier check the blocking diode it has a habit of causeing poor ignitons. Also check the connections on the lamp
Posted by Randy Stankey (Member # 64) on 09-05-2000, 11:21 AM:
If your theatre is 6 months old and you put an average of 50 hours on your projectors per week, you would have put 1,200 hours on that lamp.If your lamp is 4,200 watts (I don't recollect you mentioning the wattage) you're right at about the "safe" life expectancy of the lamp. If the lamp is larger than 4,200 watts, you're definately over. (Larger lamps have shorter life expectancy)
Let the lamphouse cool off. (Maybe even wait till opening the next day) Open the lamphouse and look at the bulb...
((((PUT ON YOUR SAFETY GEAR))))
Is the glass blackened? Have the metal ends turned color? Do the electrodes inside the glass look burned up (melted)? Compare the lamp in question with a new one if you want.
Gordon is right... check the connections while you're at it.
If it looks bad change it. Heck, if it turns out that it really isn't the lamp, you could always put the old one back in and continue the trouble shooting. It's just that changing the lamp is the one of the easiest things to fix. I think you should always try the easiest fixes first. (IMHO)
Posted by Matt Ashburn (Member # 573) on 09-05-2000, 11:37 AM:
Thanks for the suggestions. Yeah, the easiest things should be done first. BTW: the wattage of the bulb is 1600 W.
Posted by Matt Ashburn (Member # 573) on 09-05-2000, 11:40 AM:
One more thing: the theatre doesn't have proper safety gear. All they have is a face shield (from Lowe's) that will probably protect the face and upper neck, but the only gloves they use are cotton gloves that were laying around. I have refused to handle the bulbs because of this, and I was wondering what safety equipment I could buy that could protect me int he event of a bulb explosion. I'm guessing that the equipment is availble locally (like at Lowe's or another store), but have heard differing opinions on what to use.Thanks again,
-Matt
Posted by John Pytlak (Member # 331) on 09-05-2000, 12:14 PM:
Most theatre equipment dealers can supply the proper safety equipment for handling xenon lamps. You might also check out "Safety Equipment and Clothing" in the phone book Yellow Pages, or magazines like "Industrial Hygiene News": http://www.rimbach.com As noted in many other posts, NEVER handle xenon lamps without the proper safety gear to protect your eyes, neck, hands/wrists, and torso.------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Posted by Pat Moore (Member # 380) on 09-05-2000, 02:13 PM:
Matt; Still like to know the operating current of the lamp when it's running, general condition and appearance of the lamp, etc. When it is operating, is the arc steady ir does it waver/flicker?When the lamp tries to strike the lamp, does it do it automatically? That system should achieve around 120VDC Open Circuit before igniting.
A 1600W bulb's nominal current is around 65-70 Amps. That power supply is capable of 1600-2000W operation so it has multiple primary and secondary taps on the transformer. The wrong combination of taps might cause a problem.
Pat
Posted by Randy Stankey (Member # 64) on 09-05-2000, 03:12 PM:
Do you know anybody who's a welder or a machinist? or can you go to a welder's (or machinist's) supply place?The heavy leather gloves and apron that welders wear would be good. If you have a face mask but you don't think it's strong enough to save you, maybe a pair of safety goggles would be good to wear under the shield.
Fail that, the next thing I'd try would be a good heavy hunting jacket like "Carhart's". You could get some "Carhart's" at the sporting goods store. If it was me, I'd get somebody to buy me a new one and I'd donate my old one to the cause. But then again, I'm from Pennsylvania. We practically LIVE in Carhart's. I think they issue every Pennsylvanian a set at birth! 
Posted by Gordon McLeod (Member # 33) on 09-05-2000, 06:34 PM:
Since it is a LUMEX its maximum bulb is 2KW
The ignitors in them are flakey at best
I have often mounted a used ORC or LP ignitor in them. It is a pain as there is no way to manually energize the ignitor