Mitsubishi Electric PUY-A12NKA7, Руководство по обслуживанию

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Thermistor R0 = 15 k
"
± 3%
B constant = 3480 ± 2%
t (
:
): R
t
=15exp{3480( 273+t – 273 )}
T (˚F): R
T
=15exp{3480( 273+(T– 32)/1.8 – 273 )}
10-7. HOW TO CHECK THE COMPONENTS
<Thermistor feature chart>
Low temperature thermistors
• Thermistor <Liquid> (TH3)
• Thermistor <2-phase pipe> (TH6)
• Thermistor <Ambient> (TH7)
• Thermistor <Suction> (TH32)
32˚F [0
:
] 15 k
"
50˚F [10
:
] 9.6 k
"
68˚F [20
:
] 6.3 k
"
77˚F [25
:
] 5.2 k
"
86˚F [30
:
] 4.3 k
"
104˚F [40
:
] 3.0 k
"
1 1
Thermistor R120 = 7.465 k
"
± 2%
B constant = 4057 ± 2%
t (
:
): Rt =7.465exp{4057( 273+t – 393 )}
T (˚F): R
T
=7.465exp{4057( 273+(T– 32)/1.8 – 393 )}
1 1
68˚F [20
:
] 250 k
"
86˚F [30
:
] 160 k
"
104˚F [40
:
] 104 k
"
122˚F [50
:
] 70 k
"
140˚F [60
:
] 48 k
"
158˚F [70
:
] 34 k
"
176˚F [80
:
] 24 k
"
194˚F [90
:
] 17.5 k
"
212˚F [100
:
] 13.0 k
"
230˚F [110
:
] 9.8 k
"
High temperature thermistor
• Thermistor <Comp. surface> (TH33)
• Thermistor <Discharge> (TH4)
0
10
20
30
40
50
− 20 − 10 0 10 20 30 40 50
− 4 − 14 32 50 68 86 104122
:
°F
Temperature
Resistance (k
"
)
500
400
300
200
100
0
25
50 75 100 120
77
122 167 212 248
:
°F
Temperature
Resistance (k
"
)
32˚F [0
:
] 180 k
"
77˚F [25
:
] 50 k
"
122˚F [50
:
] 17 k
"
158˚F [70
:
] 8 k
"
194˚F [90
:
] 4 k
"
Thermistor R50 = 17 k
"
± 2%
B constant = 4170 ± 3%
t (
:
): Rt =17exp{4170( 273+t – 323 )}
T (˚F): R
T
=17exp{4170( 273+(T– 32)/1.8 – 323 )}
1 1
Medium temperature thermistor
• Thermistor <Heat sink> (TH8)
200
150
100
50
0
25 50 75 100 110 125
77 122 167 212 230 257
:
°F
Temperature
Resistance (k
"
)
1 1
1 1
1 1
OCH636A