Sanyo QuaDrive PLC-HF10000L, Service Manual

Page: 162 / 280

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Troubleshooting
temperature monitor operation
The temperature monitor system is provided to prevents
damage of optical components (the LCD panel and po-
larization film etc.) inside a projector from overheat.
Two protection systems are provided. Each system op-
eration as follows :
the temperature monitor -1:
●
to control the air-flow of the cooling fans.
The CPU checks the temperature and atmospheric
pressure inside a projector. It checks a temperature
using temperature sensors IC8811 and IC8856, and it
checks an atmospheric pressure using pressure sen-
sor-IC886. The CPU judges data from sensors and
controls the air flow of the cooling fans so the tem-
perature inside the projector is maintained to normal
temperature.
●
to shut down the projector urgently.
The IC301 checks temperature of LCD panel periph-
ery (IC8856) and intake air (IC8811). If each part tem-
perature reaches abnormal temperature, the CPU will
turn off the projector, and will blink WARNING TEMP.
indicator at intervals of 0.5 seconds. Cooling fans op-
erate until temperature returns to normal.
the temperature monitor -2 :
●
temperature check of lamps :
Temperature switches (SW903, SW904) are placed
near the lamps. Temperature switches will operate,
if temperature reaches 100 ºC. When temperature
switches become open, they cut off 12 line, the pow-
er failure "PF_TH" signal become Low, and then the
IC301 will shut down the projector, and indicates the
error on the projector with the LED indicators ( LAMP
indicator : On, other indicators: blinking).
NOTE : SENSORS OPERATION
■
The sensor's operation is as follows:
IC886 : For FAN control
IC8856 : Inside air temperature monitor (Panel)
IC8811: Inside air temperature monitor (Room)
LED indicators
When the internal temp
error, the WARNING TEMP.
indicator will be blinking.
W h e n t h e t e m p e r a t u re
around the lamp1 or 2 rises
abnormally , the LAMP indi-
cator is lighting and other
indicators are blinking.
The temperature
switch is operated?
If the temperature
around FET goes up
abnormally, a PFC cir-
cuit will be shut down.
The temperature switch is
operated?
When the temperature
around a lamp driver reach-
es 85 degrees, the lamp bal-
last will be shut down and
a lamp error signal changes
from L to H.
Temperature sensors location can be seen on
"protections"( page-8).
Temperature Abnormality
PFC_SW3 PFC_SW4
AC
F901
FUSE
SW901
MAINS
SWITCH
LINE
FILTER
K6C
POWER(AC)
K6A
LAMP1
Cooling
Fans
THERMAL SW
SW904
THERMAL SW
SW903
LAMP COVER
SW
SW902
PFC
BALLAST1
CN1B CN3B
LAMP2
BALLAST2
CN1C CN3C
K16A
K16B
K16C
POWER(DC)
FANNET
Cooling
Fans
FAN
CONTROL
FAN
CONTROL
IC5201
FPGA
IC1801
I/O EXPANDER
IC4801/IC4811
I/O EXPANDER
IC886
PRESS SENSOR
IC8856
TEMP.SENSOR
<PANEL>
IC8811
TEMP. SENSOR
<ROOM>
IC301
SCALER
PFC_SW
S-6V
S9.6V
S6V
S-6V
S9.6V
S6V
PFC_SW
S12V
12V
POWER_ON_SW POWER_ON_SW
PFC_SW3
PFC_SW4
P.FAIL
PF_TH
P.FAIL
S16V
S16V
IIC
IIC
PF_FAN
Lamp Mode Lamp1 Lamp2 Lamp1/2
PFC_SW3 H L H
PFC_SW4 L H H
Power-on: H
Stand-by: L
Power-on: H
Stand-by: L
PFC_SW
PF_FAN
POWER
Check FAN
circuits.
Check the
temperature
switches.
Opens at 80ªC