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LAMP FOCUS PROCEDURE

Operate the motion until the lampheads swing

outward

and shut off the

motion with the lampheads extended in the outermost position. This
provides easier access to the focus adjustments.

The two bulb centering movements (normally described as X and Y adjust-
ments, see Figure 9) are located in the sides of the lamphead. They are
approximately three inches down from the top, or window end, of the lamp-
head and immediately adjacent to the ends of the two spider legs, which are
located at right angles to each other (90 degrees apart). The adjustment
holes are closed with plugs to prevent entrance of moisture and dirt. Care-
fully remove the plugs and insert the appropriate adjustment tool (5/32" allen
wrench).

With the light operating, the operator should position himself adjacent to

either one of the X or Y adjustments so that he can view the beam from
that angle, while adjusting the other adjustment. In other words, if he posi-
tions himself adjacent to the X adjustment and views the beam from that
position, he will be able to visually assess the results of his adjustment of
the Y adjustment. The operator should alternately turn the opposite adjust-

ment first clockwise and then counterclockwise to observe the movements

of the apparent center of the beam and try to obtain symmetry

The operator should then move and reposition his body adjacent to the
other adjustment, 90 degrees removed, and then adjust the other beam
centering adjustment. The combination of movements of these X and Y
adjustments should result in a completely symmetrical beam shape when
viewed from any position.

Focus adjustment (see Figure 9): The focus adjustment is performed on

the third leg of the spider assembly and is accessible by removal of the

plug located on the front rim of the fiberglass housing assembly adjacent

to the window. On units manufactured after March 2001, the adjustment
screw is accessible from the bottom of the lamphead (Figure 9, Item 5*).
Clockwise rotation of this adjustment will move the bulb forward, or away

from the reflector, causing the beam to converge to a narrower appearing

beam. Counterclockwise will cause the bulb to be moved deeper into the

reflector, causing a divergence or spread of the beam. The operator will

have to judge which type of beam is most suitable for the intended appli-
cation or use.

After adjustment is complete, be sure to replace all plugs to prevent en-

trance of undesirable moisture and dirt into the lamphousing.

Since all of the above noted adjustments are spring loaded, there should be little or no free
movement or “backlash,” nor drifting of the adjustments due to vibration associated with
transport. The bulb should remain reasonably well focused for long periods of time. How-
ever, as the bulb ages, the cathode tip will burn back and the quartz envelope will darken,
and some minor refocusing may be required to maximize performance and appearance.