Mitsubishi Heavy Industries SRK63ZR-WF Technical Manual page 48

(c) Cooling overload protective control
(i) Operating conditions:Reset conditions
When the outdoor air temperature (TH2) has become continuously for 30 seconds at 38(37)℃ or more, with the
compressor running, the lower limit speed of compressor is brought up.
Item
Outdoor air temperature
Lower limit speed
Item
Outdoor air temperature
Lower limit speed
(ii) Detail of operation
The lower limit of compressor command speed is set to 25(30), 30(35) or 40 rps and even if the calculated result
becomes lower than that after fuzzy calculation, the speed is kept to 25(30), 30(35) or 40 rps. However, when
the thermo OFF, the speed is reduced to 0 rps.
(iii) Reset conditions
When either of the following condition is satisfied
1) The outdoor air temperature is lower than 37(36) ℃.
2) The compressor command speed is 0 rps.
(d) Cooling high pressure control
(i) Purpose
Prevents anomalous high pressure operation during cooling
(ii) Detector
Outdoor heat exchanger temperature (TH1)
(iii) Detail of operation
(Example) Fuzzy
・Model 63
Range A
Range B
Range C
・Model 71
Range A
Range B
Range C
・Model 80
Range A
Range B
Notes(1) When the outdoor heat exchanger temperature is in the range of P2 - P3, the speed is reduced by 8 rps at each 20 seconds.
Notes(2) When the temperature is P3 or higher, the compressor is stopped.
Notes(3) When the outdoor heat exchanger temperature is in the range of P1 - P2, if the compressor command speed is been maintained and the
operation has continued for more than 30 seconds at the same speed, it returns to the normal cooling operation.
Model
SRK63ZR-WF
38℃ or more 41℃ or more
25 rps 30 rps
Model
SRK71, 80ZR-WF
37℃ or more 41℃ or more
30 rps 35 rps
After lapse of 30 sec. or over
After lapse of 30 sec. or over
After lapse of 30 sec. or over
P1
Outdoor heat exchanger temperature (°C)
Unit : °C
P1 P2 P3
53 58
62
48 52
55
44 45.5
47
Unit : °C
P1 P2 P3
53 58
61
51 53
56
48 50
56
Unit : °C
P1 P2 P3
53 58
60
51 53
56
47
-
47℃ or more
40 rps
OFF
37(36) 38(37)
47℃ or more
40 rps
Note(1) Values in ( ) are for the models 71, 80.
8rps
(1)
(3)
8rps
(3)
lower limit
(3)
speed 30 rps
P2
Range B
Range C
25 26
Outdoor air temperature (°C)
Range B
Range C
16 18
Outdoor air temperature (°C)
Range B
31
Outdoor air temperature (°C)
-
'22 • SRK-T-362
ON2
ON1
40 41 46
Outdoor air temperature (°C)
(1)
0rps
P3
Range A
31 32
Range A
31 32
Range A
32
ON3
47