Film-Tech Forum ARCHIVE: CDXL-30 Bulbs and tolerances

This is topic CDXL-30 Bulbs and tolerances in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Andy Muirhead (Member # 712) on 09-02-2009, 03:27 PM:

Hi,

Anyone know the safe tolerances on these bulbs (CDXL-30 3kW)? We have one which is run at 1.5kW for 2D and 2.5kW for 3D. I usually go by 10% but have no experience of these new bulbs, but it can't be right to under run as much as this?

Posted by David Zylstra (Member # 4230) on 09-02-2009, 04:24 PM:

I know Christie has done some testing of running the CDXL lamps lower than the normal recommended amperage range. I had a CP2000H auditorium where we monitored a CDXL-45 at low power and took weekly readings of a CDXL-45 at 50% for Christie. My test data shows that we ran flat at 51% and scope at 70% (% is based on a max current of 155amps for the CDXL-45) - I could not tell you the mix of scope and flat movies across the lamp's life though. For near 130% of the warranty life the lamp ran without any issues.

My new location of all ZX projectors has many CDXL-20 and -30 lamps running lower than 70% for flat - so far after about 1,000 hours we have seen no issues.

Posted by Steve Guttag (Member # 268) on 09-02-2009, 04:30 PM:

The Christie lamps do have a very wide operating range...check their literature on what the range is. On the CDXL-30, you can go up to 120A (Whereas most 3Ks top out at 110A)...the bottom end is indeed pretty far down, as I recall.

Steve