Temperature Abnormality; System Control - Sanyo PLV-WF10 Service Manual

System Control

Note : Temperature monitor operation
The temperature monitor system protects optical components (LCD
panel, Polarization film, etc.) from the unusual overheat inside a
projector. This system is composed of two protection equipment.
Each system operation as follows ;
The temperature monitor -1;
The CPU controls Air flow.
The CPU checks the temperature by using the temperature sensor-
IC5801 and the atmospheric pressure by using pressure sensor-
IC886, inside a projector. The CPU judges data from sensors and
controls the air flow of the cooling fans so that the temperature
inside the projector may be maintained to normal temperature.
The CPU shuts down the projector compulsorily.
The CPU checks the temperatures by using the temperature sen-
sors IC2561 (near the Red LCD panel) and IC5801(inhalation air).
If each part temperature reaches to abnormal temperature(IC2561
Hot circuit
FUSE
F901
AC-INPUT
CHECK Fan
*
NOTE : TEMP. MONITOR LED OPERATION
The red LED indicates temperature monitor operation as follows:
LED off: Normal temperature.
LED flashes in 0.6 second interval: Abnormality temperature.
Does the temperature warning
indicator (red) blink?
The projector is turned off when
the temperature around the LCD
panel reaches 46 - 48 degrees.
And a temperature warning indi-
cator blinks.

TEMPERATURE ABNORMALITY -1

; 47degrees / IC5801 ; 42degrees), the CPU will shut down the pro-
jector, and will blink TEMPERATURE WARNING indicator at inter-
vals of 0.6 seconds. The cooling fans operate until the temperature
returns to normal. When the temperature returns to normal, the
indicator stops blinking. Then trace the cause of an unusual tem-
perature. And repair the projector. (Refer to the item of "temperature
abnormality" of troubleshooting.)
D7/E7
The temperature monitor -2 ;
The temperature switches shut down the projector com-
pulsorily.
Temperature switches (SW903/904) are arranged near the two
lamps. If a temperature of lamp reaches an unusual temperature,
the temperature switch will operate. The lamp ballast units shut
down, then the projector is turned off when the temperature switch-
es operate.
INTERLOCK SW
SW902
Refer to page 32.
FANS
FANS
CHECK !
LAMP
REPLACE
WARNING
TEMP.
READY
LAMP
INDICATORS
NOTE : CPU OPERATION
CPU (IC801) performs an input check by the IIC-SDA
signal pin.
When it has detected abnormal condition, CPU turns off
the projector compulsorily. Cooling fans operate until
temperature returns to normal. Moreover, a projector
cannot be turned on during this period.
Note :
(1) If other protection equipment (The function of signal check of
"Power failure", The temperature monitor-1, etc.) are rightly operat-
ing, the lamp does not become an unusual temperature. So, the
temperature monitor-2 rarely operates. However, when those pro-
tection equipment do not operate with fault, this temperature moni-
tor-2 operates and covers the broken protection equipment. If this
temperature monitor-2 operates, it is thought fault of other protec-
tion equipment. Trace the fault of other protection equipment and
the causes of an unusual temperature. (Refer to the item of "tem-
perature abnormality" of troubleshooting.)
(2) The CPU does not check the operation of temperature switches
(SW903/904). Therefore, the TEMPERATURE WARNING indicator
does not blink when the temperature switch (SW903 or 904) oper-
ates and the projector is shut down.
ASS'Y POWER
DC out
16V /9V /6.25V /-6V
POWER
CONTROL
FAN
ON/OFF CONTROL
I / O
EXPANDER
SUB POWER
CHECK !
-30-
Troubleshooting
AC
Always
DC out
SWITCH
Switched
CPU IC801
and
I / O
EXPANDER
IC1831