50
10-7. HOW TO CHECK THE COMPONENTS
<Thermistor feature chart>
Low temperature thermistors
• Thermistor <Outdoor pipe> (TH3)
• Thermistor <Outdoor 2-phase pipe> (TH6)
• Thermistor <Outdoor> (TH7)
Thermistor R0 = 15k
'
± 3%
B constant = 3480 ± 2%
R
t
=15exp{3480( 273+t
–
273 )}
0
:
15k
'
10
:
9.6k
'
20
:
6.3k
'
25
:
5.2k
'
0
:
180k
'
25
:
50k
'
50
:
17k
'
70
:
8k
'
90
:
4k
'
30
:
4.3k
'
40
:
3.0k
'
1
1
Thermistor R50 = 17k
'
± 2%
B constant = 4150 ± 3%
R
t
=17exp{4150( 273+t
–
323)}
1
1
Thermistor R120 = 7.465k
'
± 2%
B constant = 4057 ± 2%
R
t
=7.465exp{4057( 273+t
–
393)}
1
1
Medium temperature thermistor
• Thermistor <Heat sink> (TH8)
20
:
250k
'
30
:
160k
'
40
:
104k
'
50
:
70k
'
60
:
48k
'
70
:
34k
'
80
:
24k
'
90
:
17.5k
'
100
:
13.0k
'
110
:
9.8k
'
High temperature thermistor
• Thermistor <Discharge> (TH4)
0
10
20
30
40
50
-20 -10 0
10 20 30 40 50
Temperature (
:
)
Resistance (k
"
)
200
150
100
50
0
25
50
75
100
125
Temperature (
:
)
Resistance (k
"
)
500
400
300
200
100
0
25
50
75
100
120
Temperature (
:
)
Resistance (k
"
)
OC359A-2.qxp 06.7.12 3:07 PM Page 50
