Mitsubishi Electric CITY MULTI PUMY-P112VKM6, Руководство по обслуживанию

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OCH790 _92
8-8. How to check the components
8-8-1. Thermistor feature chart
■
Low temperature thermistors
• TH2 (HIC pipe)
• TH3 (Outdoor liquid pipe)
• TH6 (Suction pipe)
• TH7 (Ambient)
Thermistor R0 = 15 kΩ ± 3 %
B constant = 3480 ± 1 %
R
t
=15exp{3480( 273+t – 273 )}
1 1
Temperature Resistance value
0°C [32
°F
] 15 kΩ
10°C [50 °F ] 9.6 kΩ
20°C [68 °F ] 6.3 kΩ
25°C [77 °F ] 5.2 kΩ
30°C [86 °F ] 4.3 kΩ
40°C [104 °F ] 3.0 kΩ
0
10
20
30
40
50
− 20 − 10 0 10 20 30 40 50
− 4 − 14 32 50 68 86 104 122
Temperature
Resistance (k
Ω
)
(°C)
(°F)
■ Medium temperature thermistor
• TH8 (Heat sink)
Thermistor R50 = 17 kΩ ± 2 %
B constant = 4150 ± 3 %
R
t
=17exp{4150( 273+t – 323)}
1 1
Temperature Resistance value
0°C [32°F] 180 kΩ
25°C [77°F] 50 kΩ
50°C [122°F] 17 kΩ
70°C [158°F] 8 kΩ
90°C [194°F] 4 kΩ
200
150
100
50
0
25 50 75 100 125
Resistance (k
Ω
)
Temperature
(°C)
77 122 167 212 257 (°F)
■ High temperature thermistor
• TH4 (Compressor)
Thermistor R120 = 7.465 kΩ ± 2 %
B constant = 4057 ± 2 %
R
t
=7.465exp{4057( 273+t – 393 )}
1 1
Temperature Resistance value
20°C [68
°F
] 250 kΩ
30°C [86
°F
] 160 kΩ
40°C [104
°F
] 104 kΩ
50°C [122 °F ] 70 kΩ
60°C [140 °F ] 48 kΩ
70°C [158 °F ] 34 kΩ
80°C [176 °F ] 24 kΩ
90°C [194 °F ] 17.5 kΩ
100°C [212 °F ] 13.0 kΩ
110°C [230
°F
] 9.8 kΩ
500
400
300
200
100
0
25 50 75 100
120
77 122 167 212
248
Resistance (k
Ω
)
Temperature
(°C)
(°F)