-
39
-
(4)
Operation control function by the outdoor unit controller
(a)
Deciding the compressor speed
The indoor unit’s return air temperature ad the set temperature are used to carry out fuzzy calculations, then the required
speed is decided. Speed control compensation is then activated to decide the speed.
Unit required speed
( i ) Dehumidify and cooling operation
Model
Item
Units: rps
302 series
Outdoor unit
Maximum required speed
Minimum required speed
88
20
(ii) Heating operation
Model
Item
Units: rps
302 series
Outdoor unit
Maximum required speed
Minimum required speed
95
20
(b)
Compressor start control
At the point when compressor operating conditions are established, the control in either item (i) or item (ii) is executed.
( i ) The first time the compressor starts after the power is turned ON, or when the operating mode is the same as the
operating mode the previous time the compressor ran, the compressor starts 5 seconds after the compressor ON condi-
tions are established.
(ii) If the mode reverses from the previous operating mode, the 4-way valve is switched 10 seconds after the compressor’s
ON conditions are established, then 10 seconds after that, the compressor starts.
(c)
Compressor soft start control
( i ) Compressor protective start
1
1
1
1
1
1) Compressor protective start I is executed when the compressor starts.
2) Control contents
a) The commanded speed is set at 42 rps 30 seconds after the compressor starts, and the increase in speed at this
time is 6 rps / 30 seconds.
b) 4 (2:Heating) minutes after the compressor starts, the speed is set at the target speed.
(ii) Compressor protective start
3
3
3
3
3
1) The first additional time the compressor starts after the power is turned ON, compressor protective start
3
3
3
3
3
is ex-
ecuted.
2) Control content
a) Momentary stop judgment control
When 3 minutes have passed since the power was turned ON, the following judgment is implemented.
i)
When the discharge pipe temperature (Tho-D) is 15
°
C or more higher than the outdoor air temperature
(Tho-A), it is judged that an instantaneous stop is required. This control is stopped and the compressor is
started under compressor protective start I.
ii) When the discharge pipe temperature (Tho-D) is less than 15
°
C above the outdoor air temperature (Tho-A),
control changes to the operation mode judgment control in item b).
Note (1) The compressor is not started for 3 minutes after the power supply is ON.
b) Operation mode judgment control
Control changes to the following control required from the indoor units or in accordance with the SW5-4 setting
(switching between cooling/heating) in test run control.
●
When in the cooling and dehumidifying mode, control is switched to cooling start conditions judgment control
in item i).
●
When in the heating mode, control is switched to high dilution operation prevention control in item v).
i)
Cooling start conditions judgment
If any of the following conditions is established, control is switched to low speed operation control in item
iv). Also, if none of these conditions is established, control is switched to high dilution operation prevention
control in item ii).
Conditions
1
6 hours have passed since the power was turned ON.
2
The outside temperature (Tho-A) is 5ºC or higher.
