Explanation On Schematic Diagram; Master Unit Setting Dip Switch; Master Control System; Input And Output Control Quantity - Gree GMV-S120WL/A-S Service Manual

Remark: Only one fan can be set to emergency mode. If two or more fans are set to
emergency mode, outdoor unit will report emergency operation setting error.
Static Pressure Setting DIP Switch (SA6)
Master Unit Setting DIP Switch (SA8)
If you turn the SA8 DIP switch on main board from position ―1‖ to position ―0‖, the
corresponding unit will become the master unit. ―1‖ means slave unit while ―2‖ is a null digit. Only
one master unit is allowed for one system. The rest of the units should be slave units. Otherwise,
outdoor unit will report ―No Master Unit‖ or ―Multiple Master Units‖ error (It is a factory setting, no
need of change).

Explanation on Schematic Diagram

Master Control System

 Function: It is connected with the indoor section through 2-core (4-core needle stand)
communication wire. When it receives on or off signal, mode signal, set temperature,
ambient temperature from indoor unit, it will decide the operating mode of outdoor unit
and calculate the proper operating frequency according to capacity, which will be sent
back to the drive control system through 2-core (4-core needle stand) communication
wire. It will also adjust fan speed according to system pressure and monitor the
temperature sensed by each temperature sensor, the operating status and protection in
real time, so as to make sure the whole system can work normally and reliably. If
malfunction occurs, LED digital tubes of master control board will display the
corresponding protection code. If malfunction occurs to drive, digital tubes of indoor unit
will display drive malfunction code and LED digital tubes of master control board will
display the specific malfunction type.

Input and Output Control Quantity:

 High voltage switch is used to identify system high voltage. When the high voltage is too
high, high voltage switch will be disconnected. Main board receives the signal of high
voltage switch breaking, and then transfers the signal to controller, which will display the
error code. Unit won't start up.
 Ambient temperature sensor id used to sense the ambient temperature of outdoor unit.
Controller will calculate the corresponding capacity according to the sensed ambient
temperature.
 Defrosting temperature sensor is used to sense the actual temperature of the liquid side
of outdoor unit condenser. Controller will judge according to the sensed temperature
whether it is necessary to defrost or not.
 Condenser tube inlet temperature sensor is used to sense the refrigerant gas
temperature of condenser and judge the heating evaporation temperature.
 Condenser tube outlet temperature sensor is used to sense the liquid side temperature of
condenser for controlling the degree of sub-cooling.
 Gas separator inlet temperature sensor
 Gas separator outlet temperature sensor
 Sub-cooler liquid-extracting temperature sensor is used to sense the liquid outlet tube
temperature of sub-cooler and judge the sub-cooling status in order to calculate the
degree of sub-cooling.
 Sub-cooler gas outlet temperature is used to sense the gas outlet tube temperature of
sub-cooler for controlling the degree of superheating of sub-cooler bypass flow.
 Discharge temperature sensor is used to sense the discharge temperature of outdoor
GMV5 Home DC Inverter Multi VRF Units
0
Static pressure setting DIP switch SA6
DIP1
0
1
0
1
1
Static pressure(Pa)
DIP2
0 0
0 20
1 50
1 80
47
Error of fan 2