Control Function Of The Units; The Capacity Of Compressor Output; Compressor Startup Control; Outdoor Fan Control - Gree GMV series Service Manual

Dc Inverter VRF plus Water Heater Solution Service Manual

2 CONTROL FUNCTION OF THE UNITS

2.1 Control Function of the Outdoor Unit
1）The Capacity of Compressor Output
The capacity of compressor is counted by the indoor load or hydro-box load, and the former relates to running
or stopping of indoor unit ,the setting temperature,the outdoor temperature and the indoor temperature. the
hydro-box load relates to running or stopping of hydro-box,the setting water temperature, actual temp, the outdoor
temperature and the indoor temperature.Then the capacity of compressor output will match the indoor loads and
hydro-box optimally.
2）Compressor Startup Control
◆ Except the system receiving the stop signal,if the system starts,it must run for 6min at least.Once the
compressor stops,it restarts after 3min later at least.
◆ The compressor has to be stopped for at least 3min once it stops. During this 3min, the compressor can't
started up.
◆When the complete unit is under heating mode and the capacity requirement of each indoor unit is 0, the
compressor must be stopped.
◆Initialization Control of Compressor

3) Outdoor Fan Control

The closed-cycle control of direct current motor is adopted: it detects the actual rotational speed of
motor( feedback pulse of motor) and then compares it with the target rotational speed. Finally it output proper duty
ratio to change the rotational speed so that the decination can be cleared.
the frequency of fan adjusts from 0 to 55Hz. 0 means the stop of fan and 50 means fastest speed of fan.
◆ Cooling Mode:
Initialization: Within 3min after the unit is started, set the initial fan frequency according to outdoor
temperature. This is applicable when the unit is initially started or the mode of the unit is shifted.
Output
T≤0
0＜T≤12
12＜T≤20
Fan
Frequency
20＜T≤35
35＜T≤40
Fan Control after 3min
a）Frequency of fan is adjusted in 3min later according to the change of pressure.
b）The max.frequency of fan is 50HZ and the min. is in the below table.(OHz means the stop of fan
regarding the drive of fan)
P＜25%
0Hz
0Hz
10Hz
28Hz
36Hz
T＞40 Max.
Remarks：Max. value is 50Hz
25%≤P＜ 40%≤P＜
40% 60%
0Hz 1Hz
1Hz 1Hz
15Hz 20Hz
33Hz 38Hz
38Hz 41Hz
Max. Max.
CONTROL
60%≤P＜
P≥80%
80%
1Hz 1Hz
1Hz 5Hz
23Hz 25Hz
44Hz Max.
44Hz Max.
Max. Max.
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