Compressor Soft Start Control - Mitsubishi Electric FDT125VNVF Technical Manual

(3)

Compressor soft start control

(a) Compressor protection start I
[Control condition] Normally, the compressor operation frequency is raised in this start pattern.
[Control contents] a) Starts with the compressor's target frequency at A rps.
(b) Compressor protection start III
[Control condition] Number of compressor starts is only 1 counted after the power supply breaker ON.
[Control contents]
1) Low frequency operation control during cooling/dehumidifying
[Control condition] Upon establishing the conditions of compressor protection start III, the low frequency
[Control contents]
2) Low frequency operation control during heating
[Control condition] When the conditions of compressor protection start III are established and one of following conditions
[Control contents]
However, when the ambient air temperature (Tho-A) is 35°C or higher during cooling/
dehumidifying or the indoor return air temperature (Th
starts at C rps.
b) At 30 seconds after the start of compressor, its target frequency changes to B rps and the
compressor is operated for 2 - 4 minutes with its operation frequency fixed at B rps.
Model Operation mode
Cooling/Dehumidifying
100-140
Cooling/Dehumidifying
200, 250
Operates by selecting one of following start patterns according to the operation mode and the
outdoor air temperature (Tho-A).
operation control is performed during cooling/dehumidifying.
➀ Starts with the compressor's target frequency at A rps. When the outdoor air temperature
(Tho-A) is 35°C or higher, it starts at C rps.
➁ At 30 seconds after the compressor start, the compressor's target frequency is changed to B
rps and the compressor's operation frequency is fixed for 10 minutes.
Model
100-140 Cooling/Dehumidifying
200, 250 Cooling/Dehumidifying
➀ and ➁ is satisfied, the low number of revolutions operation control is performed during heating.
➀ At 30 minutes or more after turning the power supply breaker on
➁ Compressor underneath temperature (Tho-H) is 4°C or higher and the difference from the
outdoor air temperature (Tho-A) becomes 4°C or higher. [model 200, 250 only]
➀ Starts the compressor with its target frequency at A rps. However, when the indoor unit
return air temperature (Th
➁ At 30 seconds after the start of compressor, the compressor's target frequency is changed to
B rps and the compressor's operation frequency is fixed for 10 minutes.
Model
100-140
200, 250
A rps
55
Heating 55
55
Heating 55
Operation mode A rps
-A) is 25°C or higher, it start at C rps.
I
Operation mode A rps
55
Heating
55
Heating
318
- -
'12 • PAC-T-174
-A) is 25°C or higher during heating, it
I
B rps C rps
55
55
55
55
B rps
55 55
55 30
B rps
55
30
30
30
30
30
C rps
30
30
C rps
30
30