5-20
94MS20 Rev. B4
Lamp Head Blowers
The lamp head blowers are controlled by the printed circuit board to
provide the correct cooling to the lamp. During warm-up, the blowers
are off or run very slowly. At idle and during low exposure, the blowers
vary in speed. Both at high exposure and cool-down the blowers run at
full speed.
A symptom of a defective blower would be: during high power exposure,
after approximately 10 seconds, the lamp extinguishes and requires 2 to
4 minutes to restart. One blower will speed up to compensate for the
defective blower or low power. When the unit switches to high power,
the additional heat causes one of the lamp thermostats to open. (See also
Interlock System for information on the thermostats.)
To test the blowers, turn the power supply main switch on then off. During
the cool-down cycle, place a piece of paper over each intake vent located
on the lamp end. The paper should be drawn to the lamp end. If one lamp
end does not draw, that blower is suspect.
To replace the blower in the lamp head, see Opening Lamp Head.
Blown Fuse on PC Board
If the fuse blows on the printed circuit board, check if the fuse is a 5 amp
fuse.
The printed circuit board drives five or six circuits: the lamp head blowers,
shutter motor, power supply blower, and the relays. To find the cause:
•
Unplug the unit and replace the fuse; then disconnect the wires to the
lamp head on terminals 5 (blue wire) and 6 (red wire), and disconnect
one of the wire nuts connecting the blower in the power supply. The
relay coils rarely cause any problem.
•
Plug in the unit and turn on the power switch for 10 seconds.
•
If the fuse blows, the problem is either: the p.c.board or in one of the
relay coils.
•
If the fuse does not blow the problems is either: the power supply blower,
lamphead blower or shutter motor.
•
Unplug the unit and reconnect the red wire to the terminal strip #6.
•
Plug in the unit and turn on, then off. The shutter should now turn. If the
fuse blows, the problem is in the shutter motor or wiring to the motor.
•
Unplug the unit and connect the blue wire to the terminal strip. Turn on
the unit, then off for the cool-down cycle to test the lamphead blowers. If
the fuse blows during this test, the problem could be with either of the
two blowers in the lamp head. Normally, when the coil on a blower fails,
the coil will become discolored. See section Opening Lamp Head.
•
If the fuse has not blown throughout the test, the power supply blower is
suspect.
Summary of Contents for OLITE
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