Olec OLITE, Руководство по обслуживанию

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94MS20 Rev. B4 5-1
5. General
Path of Power to the PC Board
This section is useful when there is no power reaching the PC board (no
LEDs lighted). Before tracing the power, check the fuse on the PC board
and the incoming power.
The power cord enters the rear of the unit. The two hot conductors are
connected by wire nuts to wires that are in turn connected to the front of
a terminal strip. One of these two wires passes through a fuse and on
208/240V~ 60Hz units is then connected to a voltage selector switch,
then is connected to taps on a step-down autotransformer. This
transformer is located under the terminal strip on the component bracket
near the dividing wall. The transformer tap marked 120V~ becomes the
unit common and returns to the terminal strip. The other line wire is
connected to the transformer common and becomes the hot 120V~ lead
to the PC Board and also returns to the terminal strip. The power is
distributed from the strip and a pair of wires goes to the PC board.
Interlock System
The internal interlock system serves two purposes. The first is for operator
safety by insuring the safety glass is in place before operation. This glass
filters short UV radiation and covers the high voltage lamp terminals.
This interlock also protects from overheating by traveling through two
thermostats in the lamp head. There is also an outlet on some equipment
marked “interlock” and is not used in this equipment.
The internal interlock is a loop that travels through the light head, passing
through the glass switch and two thermostats. This interlock is in series
with the control circuit of the large relays in the power supply. When the
interlock is opened, the relays will open and cut the power to the lamp
terminals. The PC board senses the drop in voltage and closes the shutter.
The first place to check is the glass switch. The switch lever is located
near the edge of the glass on the end of the lamp where the cable enters.
By releasing the glass, the lever can be seen. If the lever can slip past the
glass, it should be bent slightly toward the reflector. If the switch is closed,
the loop can be traced. First measure the voltage between lamp wires (#4
V~ Common) and wire (#10 Interlock). The presence of voltage between
these terminals indicates an open loop. This loop travels to the lamp
head on wire (#10), then to the glass switch, the far end thermostat, the
near end thermostat and terminates on wire (#4). The thermostats are
mounted in the air tubes leading to the lamp. There are no splices in the
air tubes.