Film-Tech Forum ARCHIVE: New xenons too hot

This is topic New xenons too hot in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Phil Blake (Member # 2012) on 07-25-2004, 12:03 AM:

Hi All , this is an interesting one , all three Cinemeccanica lamps have been running 2k Osram xenons at 90 amps the Vic 5 shutter housing were warm we have fitted new 2k Osram xenons to the lamps , all focused in correctly , no other major changes were made , now all three Vic 5 shutter housings are too hot to touch ! , have Osram changed their xenons ' or am I missing something ?

Posted by Michael Schaffer (Member # 1204) on 07-25-2004, 12:46 AM:

90 amperes is a little stiff for 2k lamps. They are happier around 80.

Posted by Stephen Jones (Member # 16) on 07-25-2004, 10:19 PM:

Hi Phil i think 90 amps is way to high,I run mine on 70 amps with no problems at all.On the sheet that comes in the box it says 70 - 80 amps.Are you using Osram 2000k SHSC lamps?

Steve [thumbsup]

Posted by Michael Schaffer (Member # 1204) on 07-25-2004, 10:58 PM:

Another problem source I can think of, though I am not familiar with these lamphouses, so you have to look into that yourself or await feedback from other members: sometimes the dichroic coating on the reflector gets burned out and then it reflects more heat energy to the front. I had this with some Highlight consoles. They were so hot you really couldn't rest your hand on them for more than a second. After I put in new reflectors, the problem went away (and there was also much more light output of course).

Posted by Phil Blake (Member # 2012) on 07-25-2004, 11:09 PM:

In reply to Steven , yes they are Osram 2000k SHSC lamps .
Thanks Micheal this may be the problem . In fact we are running the lamp in cinema 3 at about 80 amps as it has small screen , but even that one is roasting at 80 amps, and only since new xenon went in.

Posted by Michael Schaffer (Member # 1204) on 07-25-2004, 11:41 PM:

Best to ask Gordon. He is very familiar with Cinemeccanica and can tell you exactly what type of reflector they have.

Posted by Robert L. Fischer (Member # 2424) on 07-25-2004, 11:49 PM:

We run our 2k lamps between 75 and 80.

Posted by Stephen Jones (Member # 16) on 07-26-2004, 12:34 AM:

Hi again Phil. Being a smaller screen you could try 70-75 amps and see if it helps.I assume all your blowers in the lamp house are operating as I have had a couple of these go in the Cinemecanica consol units and a lot of heat occured in the area you mentioned also might pay to see if your exhaust fans are operating ok and drawing enough air through the lamphouse as I have had these start to lose thier efficiency as bearings start to fail or some kind of blockage some where all worth checking anyway .To my knowledge I dont think Osram have made any changes to that lamp as I am useing them here In 5 screens (our smaller houses)with no changes in heat output in Kinoton consol's.Apart from that I cant think of anything else at this stage as you mentioned that they are alighned and focused ok so that rules that out.

Steve [beer]

Posted by Gordon McLeod (Member # 33) on 07-26-2004, 10:03 AM:

If the lamp is focused to far back in the reflector then it will blister and over heat
There are two different console versions one has the reflector and ignitor in a pressurized box the other has the assembly swing out
check the fan air connections as in several it is via a hose that may have got crimped or folded when the lasmp was installed
Is the glass air tube aimed properly? also sometimes after working on them the blowers need to be cleaned and the bearings checked as they don't come up to speed

Posted by Phil Blake (Member # 2012) on 07-31-2004, 07:43 AM:

we have the pressuized box model.

I have refocused and dropped amps down, it has made some difference , maybe I should check the bklower out.

Posted by Alexandre Chagas (Member # 2613) on 08-11-2004, 08:58 PM:

Hi people !
I´m feeling very happy to give my first contribuition!
I´m from Brazil and just started learn about repair projector and lamphouses.
Let me explain a particular case with a Zenith X3000H and the Victoria 5 with the same caracteristic of too hot.
1 - the fan was too low
2 - the conections of air ways were no good
After these maintnence the problem continued.
So i noticied that some eletrical conections were bad (i don´t known the word in inglish but is like a green colored)
After to correct that the problem desappear

Posted by Michael Schaffer (Member # 1204) on 08-11-2004, 09:02 PM:

The green stuff is called mildew in English.

Posted by Gordon McLeod (Member # 33) on 08-11-2004, 09:17 PM:

No it is corrosion (mildew is a mold)

Posted by John Pytlak (Member # 331) on 08-11-2004, 09:23 PM:

The green color is usually copper corrosion, and is a copper compound.

http://www.corrosion-doctors.org/Artifacts/Patina.htm

quote:
Patina Definition
The spontaneous surface corrosion of copper and its alloys has been used for centuries to create a spectrum of colors and hues controlled by the nature of the alloy and its relation to the environment. Patina is usually a green or brownish film formed naturally on copper and bronze by long exposure or artificially and often valued aesthetically for its color...

Posted by Michael Schaffer (Member # 1204) on 08-12-2004, 01:46 AM:

I know, Gordon. I thought it was obvious it was a joke.

Posted by Daryl C. W. O'Shea (Member # 1303) on 08-12-2004, 02:54 AM:

What was, your command of the English language? [Big Grin]