101
OCH634C
8-8. HOW TO CHECK THE COMPONENTS
<Thermistor feature chart>
Low temperature thermistors
• Thermistor <HIC pipe> (TH2)
• Thermistor <Outdoor liquid pipe> (TH3)
• Thermistor <Suction pipe> (TH6)
• Thermistor <Ambient> (TH7)
0
:
15 k
"
10
:
9.6 k
"
20
:
6.3 k
"
25
:
5.2 k
"
30
:
4.3 k
"
40
:
3.0 k
"
Thermistor R0 = 15 k
"
± 3 %
B constant = 3480 ± 2 %
R
t
=15exp{3480( 273+t – 273 )}
1
1
Thermistor R120 = 7.465 k
"
± 2 %
B constant = 4057 ± 2 %
R
t
=7.465exp{4057( 273+t – 393)}
1
1
20
:
250 k
"
30
:
160 k
"
40
:
104 k
"
50
:
70 k
"
60
:
48 k
"
70
:
34 k
"
80
:
24 k
"
90
:
17.5 k
"
100
:
13.0 k
"
110
:
9.8 k
"
High temperature thermistor
• Thermistor <Compressor> (TH4)
0
10
20
30
40
50
-20 -10 0 10 20 30 40 50
Temperature (
:
)
Resistance (k
"
)
500
400
300
200
100
0
25
50
75
100
120
Temperature (
:
)
Resistance (k
"
)
0
:
180 k
"
25
:
50 k
"
50
:
17 k
"
70
:
8 k
"
90
:
4 k
"
Thermistor R50 = 17 k
"
± 2 %
B constant = 4170 ± 3 %
R
t
=17exp{4170( 273+t – 323)}
1
1
Medium temperature thermistor
• Thermistor <Heat sink> (TH8)
200
150
100
50
0
25
50
75 100 110 125
:
Temperature
Resistance (k
"
)
