P3D Re: Projection Lamp Tips

[WDuggan3D@xxxxxxx]

Projection Lamp Tips (Revised 09/30/97) by 
William A. Duggan, APSA
 
	1.  ENG (120 volt, 300 watt) AV/Photo  projection lamps, 
the brightest lamps for the Brackett Dissolver and older Kodak 
Carousel and olderEktagraphic projectors, and EXW (82 volt, 
300 watt) lamps, the brightest for the Ektagraphic III projectors, 
have an expected life of about 15 to 18 hours, but newer, 
improved ENG-5 (125 volt 300 watt) and EXW-5 (86 volt, 300 
watt) lamps (made by Sylvania and Wiko, and perhaps others) 
have a slightly higher voltage and  heavier filament and last 
much longer, perhaps over 100 hours.  These "-5" lamps are 
available from Audio Visual Express, Inc., P. O. Box 442, 
Addison, IL 60101, USA  ( Phone 1-800-243-2749)   as low 
as $12.00 to $14.00 per lamp in quantity plus shipping and 
handling charge.  Retail photo stores often charge $22.00 to 
$32.00 for  ENG and EXW lamps and don't know about 
ENG-5 or EXW-5 lamps.  ELH-5 and EXR-5 lamps also have 
a longer life than ELH and EXR lamps, the "normal" or medium 
bright lamps that come with new projectors.

	2.  Projection lamps fail:   a)  As the filament stretches 
and sags to the breaking point;    b) When cold air is blown 
over the hot glass after the lamp is turned off;    c)  If the 
projector or lamp module is bumped while the lamp is still hot;   
 d)  If the lamp has been touched by bare fingers; or   e)  If a 
voltage spike higher than the lamp's rated voltage maximum 
hits the lamp (voltage varies as lamps come on and go off 
when projectors are connected to the same circuit for fade 
dissolve and/or multimedia projection). 

	3.   To extend the rated hours of any projection lamp:    
a)  Keep a record of projection hours on masking tape attached 
to the back of the projector or lamp module, and as the half life 
approaches, periodically view the filament via a dental type 
mirror, and when the filament starts to sag (curve downward), r
everse the lamp (gently remove the lamp and reinstall it upside 
down);    b). Do not leave the blower running after you turn off 
the lamp;    c)   Do not bump the projector or lamp module 
while the lamp is hot;    d)  Use white cotton gloves (the same 
gloves used in handling negatives, film, and film chips) or a 
clean handkerchief when touching, picking up, installing, or 
reversing a lamp; and    e)  Connect all projectors to a surge 
protected power strip.


(NOTE:  This article, along with other articles by William A. 
DUGGAN, APSA, P. O. Box 805, McLean, VA 22101-0805,  
Telephone:  (703) 849-0961, E-Mail:  WDuggan3d@xxxxxxx, 
is available on a PC computer diskette in AMIPRO 3.0).


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