Table of Contents
Advertisement
Troubleshooting
Temperature Abnormality
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-
IC4801/IC4811
P.FAIL
I/O EXPANDER
POWER
I/O EXPANDER
IC886
PRESS SENSOR
IC301
IC8856
IIC
IIC
SCALER
TEMP.SENSOR
<PANEL>
IC8811
TEMP. SENSOR
<ROOM>
Power-on: H
Stand-by: L
PFC_SW
IC5201
FPGA
PFC_SW3
PFC_SW4
Lamp Mode Lamp1 Lamp2 Lamp1/2
PFC_SW3
H
PFC_SW4
L
AC
F901
SW901
FUSE
MAINS
SWITCH
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)
Temperature sensors location can be seen on
"protections"( page-8).
P.FAIL
IC1801
POWER_ON_SW
POWER_ON_SW
Power-on: H
Stand-by: L
L
H
H
H
K6A
LINE
FILTER
POWER(AC)
The temperature
switch is operated?
If the temperature
around FET goes up
abnormally, a PFC cir-
cuit will be shut down.
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).
Check FAN
Cooling
circuits.
Fans
PF_FAN
FAN
CONTROL
POWER(DC)
PF_TH
S12V
12V
K16B
K16A
K6C
K16C
PFC
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.
-162-
Check the
temperature
switches.
Opens at 80ªC
Cooling
FAN
PF_FAN
Fans
CONTROL
THERMAL SW
SW904
THERMAL SW
SW903
FANNET
LAMP COVER
SW
SW902
CN1B
CN3B
BALLAST1
LAMP1
CN1C
CN3C
BALLAST2
LAMP2
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 r e
around the lamp1 or 2 rises
abnormally , the LAMP indi-
cator is lighting and other
indicators are blinking.
Advertisement
Table of Contents
