Film-Tech Forum ARCHIVE: Christie CP2210 lamp rotation

This is topic Christie CP2210 lamp rotation in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Frank Cox (Member # 6258) on 01-30-2012, 12:24 AM:

It is time to rotate the lamp in my Christie CP2210 projector since it has reached 750 hours. This is the first time I've had to do this and the instructions in the manual are unclear to me.

Here is the photo from the user's manual

The legend is:
A-Reflector
B-Anode Wire
C-Isolator Screws
D-Anode Nut
E-Cathode Screw
F-Cathode Nut
G-Cathode Clamp
H-Cathode Wire

Here are the instructions for lamp rotation:

quote:
1. Follow the same safety precautions as indicated in 4.5.6 Lamp Replacement, on page 4-7.
2. Remove the cathode cable and rotate the lamp 180°. Replace cathode cable.
3. In the Advanced Setup: Lamp History window, select the Acknowledge Lamp Rotation button.

That's it.

The instructions appear to be telling me to remove the screw that attaches the cathode wire to the projector chassis (the screw holding wire H down, located at the bottom of the photo). Even if I removed the cathode wire completely (and I don't see how I would get at the screw that holds that wire down at the top, just below the position marked G in the photo to do that), that's still not releasing the lamp so I can turn it. Plus if I do somehow manage to turn the lamp while the anode wire is still screwed down at point D, won't that put pressure on that side of the lamp while I'm turning it, and wouldn't that be a bad thing?

My guess as to what should happen here is that I should loosen both the Cathode Nut (F) and the Cathode Screw (E), then remove the Anode Nut (D), then rotate the lamp, replace the Anode Nut and tighten everything else back up.

But that's not what the manual says.

After I've done this once I'll know how to do it but right now I'm mystified.

Posted by Monte L Fullmer (Member # 2797) on 01-30-2012, 12:55 AM:

.. Interesting on not mentioning anything on anode cable removal to do the rotation ... and that Christie's requiring rotations for their bulbs for none of the other units never need any form of rotation, but just focus checkups..

Posted by Frank Cox (Member # 6258) on 01-30-2012, 12:11 PM:

I just talked to the tech that looks after my stuff here and he said that as long as the lamp looks clean and un-blackened (which it does) then rotation is not necessary. He said that he hasn't yet seen a lamp in one of the Christie projectors that actually needed to be rotated.

Easy fix -- do nothing! I think I can handle that....

Posted by Victor Liorentas (Member # 5272) on 01-30-2012, 01:04 PM:

Maybe if a bulb develops flicker the rotation would fix that but I am finding Christie,Ushio bulbs to be resistant to the need for rotation as compared to Osrams.

Mind you this is with film based Super Lumex lamphouses.

Posted by Monte L Fullmer (Member # 2797) on 01-30-2012, 06:12 PM:

Interesting is that rotation is an old practice with early Xenon bulbs due to weak airflow-which most exhaust systems were used with carbon arc lamphouse usage, thus the deposits would gather on the upper inside surface of the envelope (Osrams were good for this)...and rotation kept the deposits down to a minimum..

Also, the anode would get "ripple horns" after age due to high DC ripple from those early rectifiers..and rotation help prevent the accumulation of those "horns"...which causes the flickering since the flame is trying to find the shortest gap between the anode and cathode, and 'wanders' between the high and low points..

OSRAMS in any STRONG lamphouse using a switcher rectifier will always give problems and less life than Christie bulbs will..

Posted by Brad Miller (Member # 2) on 01-30-2012, 06:32 PM:

Monte, it has nothing to do with Strong lamphouses or switcher power supplies. Osram bulbs just don't last as long or perform as well as Ushio/Christie bulbs do...period.

I find rotating the bulb actually DECREASES usable life and performance.

Posted by Monte L Fullmer (Member # 2797) on 01-30-2012, 07:56 PM:

Sorry Brad ... All the Strongs lamphouses/consoles that I've operated using Osram bulbs, these bulbs just can get the duration on them as does the Christie when attached to a 'switcher'.

Please edit if necessary to remove my comments on this one subject..

Posted by Carsten Kurz (Member # 5396) on 01-31-2012, 01:41 PM:

Christie themselves are not taking the bulb rotation too serious - they consider it optional. Christie techs usually suggest to disable the lamp rotation warning completely. Which is probably what Christie should do by default.

Well, if you view what it is - a warning, not an error, you can just consider it as a reminder that your bulb is half way through it's warranty life.

- Carsten

Posted by Knut Erik Slettum (Member # 3588) on 02-06-2012, 01:15 AM:

I have been told the same thing as Carsten from Christie technicians. "Drop the lamp rotation. You could end up hurting the equipment more than you gain from rotating the lamp."

Posted by Steve Guttag (Member # 268) on 02-06-2012, 04:55 AM:

The only time I've found lamp rotation to benefit is with larger lamps (3K+) and that operate at a steep incline (over 5-degrees...more like 10-degrees +). The CP2210 does not have any large lamps so I can't imagine the situation where lamp rotation would benefit.

-Steve

Posted by Tony Bandiera Jr (Member # 2365) on 02-06-2012, 06:15 PM:

I agree with the masses.forget the rotation and disable the rotation warning...totally not necessary with today's bulbs and especially the lower wattage ones.