Mitsubishi SRK50ZHX-S Technical Manual page 19

(4) Cooling low outdoor temperature protective control
(a) Operating conditions: When the outdoor air temperature (Th5) is 22ºC or lower continues for 20 seconds while the
(b) Detail of operation:
1
The lower limit of the inverter command speed is set to 44 (30) rps and even if the speed becomes lower than 44 (30)
rps, the speed is kept to 44 (30) rps. However, when the thermo becomes OFF, the speed is reduced to 0 rps.
2
The upper limit of the inverter command speed is set to 50 (60) rps and even if the calculated result becomes higher than
that after fuzzy calculation, the speed is kept to 50 (60) rps.
Upper limit 50 rps
ON
Lower limit 44 rps
A
(c) Reset conditions: When either of the following condition is satisfied
1
The outdoor air temperature (Th5) is D ˚C or higher.
2
The inverter command speed is 0 rps.
(5) Heating high pressure control
(a) Purpose: Prevents anomalous high pressure operation during heating.
(b) Detector: Indoor heat exchanger sensor (Th2)
(c) Detail of operation:
(Example) Fuzzy
Notes (1) When the indoor heat exchanger temperature is in the range of B~C ºC, the speed is reduced by 4 rps at each 20 seconds.
(2) When the indoor heat exchanger temperature is in the range of C~D ºC, the speed is reduced by 8 rps at each 20 seconds. When the temperature is D ºC or
higher continues for 1 minute, the compressor is stopped.
(3) When the indoor heat exchanger temperature is in the range of A~B ºC, if the inverter command speed is been maintained and the operation has continued
for more than 20 seconds at the same speed, it returns to the normal heating operation.
(4) Indoor blower retains the fan tap when it enters in the high pressure control. Outdoor blower is operated in accordance with the speed.
¡ Temperature list
RPSmin < 88
88 < = RPSmin < 108
108 < = RPSmin
Note (1) RPSmin: The lower one between the outdoor speed and the inverter command speed
inverter command speed is other than 0 rps.
ON
Upper limit 60 rps
Lower limit 30 rps
B C D
Outdoor air temp.(°C)
After lapse of 20 sec. or over
After lapse of 20 sec. or over
After lapse of 20 sec. or over
A
Indoor unit heat exchanger temperature(˚C)
A
48.5
44
39
¡ Values of A, B, C, D
OFF
First time
Since the seconds
times
(3)
4rps
(3)
lower limit
(3)
speed 35 rps
B
B C
56 58
51.5 53.5
46.5 48.5
16
- -
Outdoor air temp. (˚C)
A B
0 3
7 10
(1) (2)
8rps
(1) (2)
4rps 8rps
0rps
C D
Unit : ºC
D
61
56.5
51.5
C D
22 25
25 28