User manual

PAL 1200, PAL 1200 E, PAL 1200 FX User Manual 21
Replacing the lamp
Discharge lamps operate under high pressure. As the lamp ages the glass envelope becomes more fragile and the risk of lamp
explosion increases. Therefore it is strongly recommended that the lamp be replaced before its rated average life has been
exceeded by 25%.
The procedure for installing the lamp is described on page 7. The position of the lamp-holder may need to be re-adjusted to
ensure optimum performance when the PAL is installed in its permanent site. The adjustment procedure follows.
Optimizing the lamp alignment
After lamp replacement it may be necessary to optimize the lamp adjustment. Thanks to some built-in sequences this adjust-
ment can be made without connecting a controller to the PAL. However, should you prefer to do the adjustment using a con-
troller you may do that as well.
1.
Switch on the PAL
and wait until the reset has finished.
2.
Via the control module select sequence ‘SP 2’, thus igniting the lamp. Before you continue with the next step
you should wait approx. 5 minutes until the lamp has reached full brightness.
3.
Select sequence ‘SP 4’, step ‘St 1’. This leaves you with an open white gobo focused to approx. 5 meters.
4.
Carefully move the mirror by hand so that the image is projected onto a flat surface.
5.
On the back of the fixture there are three lamp adjustment screws (see following diagram). Turning these
clockwise will pull the lamp towards the rear of the lamp housing, and vice versa. Center the hot-spot (the
brightest part of the image) by using the three adjustment screws. When only using one screw at a time you
will drag the hot-spot diagonally across the projected image. If you are using the standard optical configura-
tion with diffusion filter, and without the condenser lens mounted, there is practically no hot-spot. In that
case adjust the lamp until you achieve an even distribution of the light all over the image.
6.
If you are not satisfied with the light output you can try to adjust the lamp further by turning all three adjust-
ment screws a quarter turn clockwise, making sure that the hot-spot remains centered. If the result is an
improvement then repeat this procedure until there is no more improvement. If the light-output is reduced
then turn the adjustment screws a quarter turn counter clockwise and observe the result. Proceed this way
as long as the result is an improvement.
7.
Select step ‘St 2’ from the currently selected sequence (SP 4) thus inserting all three sets of CMY flags into
the beam. Now, make slight adjustments to the screws until the PAL projects an almost uniform color across
the entire image. Please note that if your are using an optical configuration without the diffusion filter and/or
with the condenser lens fitted, you will not be able achieve a completely uniform color projection.