Mitsubishi Electronics PEAD-A24AA Air Conditioner User Manual


 
32
10-6. TROUBLE CRITERION OF MAIN PARTS
PEAD-A24AA
PEAD-A30AA
PEAD-A36AA
PEAD-A42AA
Room temperature
thermistor
(TH1)
Condenser/evaporator
temperature thermistor
(TH5)
Measure the resistance with a tester.
(Part temperature 10°C (50°F) ~ 30°C (86°F))
Pipe temperature
thermistor/liquid
(TH2)
Wiring diagram
Check method and criterion
Part name
Normal
4.3kΩ~9.6kΩ
Abnormal
Opened or short-circuited
Motor
Board with build-in motor
Current detecting resistor
Regulator Hall IC
Motor winding
Power
device
Pre
driver
Vm (Power supply for motor)
Vcc (Power supply for control)
Vsp (Speed command voltage)
PG (Pulse output for rotation)
GND
10-7. Thermistor
0
10
20
30
40
50
-20 -10 0 10 20 30 40 50
< Thermistor for lower temperature >
Temperature
Resistance (K")
(˚C)
-4 14 32 50 68 86 104 122
˚F
<Thermistor Characteristic graph>
Room temperature thermistor (TH1)
Pipe temperature thermistor (TH2)
Condenser/evaporator temperature
thermistor (TH5)
Thermistor R
0=15k" ±3%
Fixed number of B=3480k" ±2%
Rt=15exp { 3480( ) }
0°C (32°F) 15k"
10°C (50°F) 9.6k"
20°C (68°F) 6.3k"
25°C (77°F) 5.2k"
30°C (86°F) 4.3k"
40°C (104°F) 3.0k"
Thermistor for
lower temperature
1
273+t
1
273