Epson EMP-TW1000 Service Manual page 45

LV Thermistor
This is a backup overheating prevention sensor mounted on the upper surface of the Optical
Engine (Prism Unit). To prevent damage to the surrounding components from overheating, the
power save controller on the MA board first provides a warning indication through the warning
indicator LED, and stops the output of the ballast when the temperature rises above a given
level.
LV Thermistor
Thermistor and Temperature Sensor Operation
Analog/Digital converters in IC550 on the MA board detect the temperatures of the Optical
Engine and Power Supply sections by means of the two thermistors at intervals of 1 second.
Based on the measurement results, the CPU controls fan operations and power supply
shutdown operations as necessary.
Condition
Normal temperature
Warning temperature
Abnormal temperature
Internal error
See Section 2.8.2 for more information on fan operation, and Section 2.9 for more information
on the LED status indicators.
SEIKO EPSON
EMP-TW1000
Figure 2-22. LV Thermistor
Table 2-4. Temperature Sensors
Warning Indicator
Off Normal operation in progress
If temperature rises any higher, projection
Flashes orange
stops.
Steady red Overheating (no projection)
Problem with fans, thermistors or
Flashes red
temperature detection circuit
2-18
Meaning
Revision:A