'20 • SRF-SM-311
-
15
-
( i ) Compressor overheat protection
(i) Purpose
It is designed to prevent deterioration of oil, burnout of motor coil and other trouble resulting from the
compressor overheat.
(ii) Detail of operation
1) Speeds are controlled with temperature detected by the sensor mounted on the discharge pipe.
Discharge pipe temperature (˚C)
Lower limit
(4)
After lapse of 1(3) min. or over
(3)
After lapse of 1(3) min. or over
(3)
After lapse of 1(3) min. or over
(3)
4 rps
4 rps
(1)
0 rps
(Example) Fuzzy
90 (95)
100 (105)
110 (115)
Notes (1) When the discharge pipe temperature is in the range of 100-110ºC (105-115ºC), the speed is reduced by 4 rps.
(2)
When the discharge pipe temperature is raised and continues operation for 20 seconds without changing, then the speed is reduced again by 4 rps.
(3) If the discharge pipe temperature is in the range of 90-100ºC (95-105ºC) even when the compressor command speed is maintained for 1(3) min-
utes when the temperature is in the range of 90-100ºC (95-105ºC), the speed is raised by 1 rps and kept at that speed for 1(3) minutes. This
process is repeated until the command speed is reached.
(4) Lower limit speed
2) If the temperature of 110ºC (115ºC) is detected by the sensor on the discharge pipe, then the compressor will stop imme-
diately.
When the discharge pipe temperature drops and the time delay of 3 minutes is over, the unit starts again within 1 hour
but there is no start at the third time.
Cooling
Heating
Lower Limit Speed
SRF25, 35
15 rps
20 rps
SRF50
25 rps
32 rps
Item
Model
(5)
Value in ( ) are for the model SRF50
( j ) Current safe
(i) Purpose
Current is controlled not to exceed the upper limit of the setting operation current.
(ii) Detail of operation
Input current to the converter is monitored with the current sensor fixed on the printed circuit board of the outdoor unit
and, if the operation current value reaches the limiting current value, the compressor command speed is reduced. If the
mechanism is actuated when the compressor command speed is less than 30 (SRF35:36) rps, the compressor is stopped
immediately. Operation starts again after a delay time of 3 minutes.
