Mitsubishi C-6919 Service Manual page 37

the regulated output at +100 V de.
Potentiometer VR901 adjust the regulated output
voltage level.
The current limiter transistor Q902 provides short
circuit protection
by
limiting the output current.
Q902 is normally biased in the no conducting state
by
the resistors R904 and R906.
In case that the 100 Volt line is suddenly is
short-circuited to ground, the voltage at the emitter
of Q902 will drop, and Q902 will turn on. This causes
Q901, Q991 and Q992 to turn off and latch in that
condition. After removal of the short-circuit fault,
operation can be restored by turning off the primary
power to the monitor for a few seconds to allow the
capacitors to discharge, and then restore power.
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