Lamp Abnormality - Sanyo PLV-WF10 Service Manual

System Control
NOTE : Light source lamp
The lamp emits light through arc discharge. To initiate arc discharge, dielectric breakdown must occur
between the lamp electrodes. The high-voltage pulse generator generates and applies high-voltage puls-
es with peak values of about 20kV between the lamp electrodes in order to generate glow discharge. This
in turn results in dielectric breakdown between the electrodes, causing a shift from glow discharge to arc
discharge.
After projector turned on, 30 seconds are required until the light output stabilizes. After the projector is
turned off, the cooling fan operates for 90 seconds to cool down the lamp and reduce gas pressure inside
the lamp. During this "cooling down" period, the projector cannot be turned on.
Hot circuit
FUSE
F901
AC-INPUT
Are you thinking about turning on the projector
without the lamp cover?
Remember that the interlock switch is opened during
disassembling the cabinet. The projector can't be
turned on. (Some of the service personnel forget it
often.) When you turn on the projector without cabi-
net, press and hold the lever of the interlock switch.
Is the Interlock switch opened?
When the lamp cover isn't attached correctly or the
boss inside the lamp cover is broken, the projector
can't be turned on. Check the boss and the Interlock
switch (SW902). Refer to figure on page 4.
NOTE :
The ready (green) LED indicates lamp monitor
operation as follows:
LED off: Lamp is being cooled.
LED on: Lamp is being lit or already cooled down.

LAMP ABNORMALITY -1

INTERLOCK SW
SW902
FANS
FANS
LAMP
REPLACE
WARNING
TEMP.
READY
LAMP
INDICATORS
Troubleshooting
ASS'Y POWER
POWER
CONTROL
FAN
ON/OFF CONTROL
I / O
EXPANDER
SUB POWER
CPU : Lamp monitor operation.
CPU performs an input check by the lamp monitor pin.
When the "H" signal continues 1 second or more continuously,
CPU judges the state to be abnormal.
When it has detected abnormal condition, CPU turns off a pro-
jector compulsorily. And CPU sets up the cooling time for 90
seconds.
The projector cannot be turned on during a cooling time.
-26-
AC
DC out
16V /9V /6.25V /-6V
Always
DC out
SWITCH
Switched
CPU IC801
and
I / O
EXPANDER
IC1831