System For Heat Pump Operation - LG MULTI V 5 Engineering Manual

SYSTEM FOR HEAT PUMP
OPERATION, 208-230V AND 460V
Figure 22: Example of a Typical Heat Pump Operation Power Wiring and Communications Cable Schematic.
3 Phase 3 Wires
Power supply
60Hz 208-230V or
60Hz 460V
Main Switch
Power supply
1 Phase 60Hz
208-230V
L1 L2
Disconnect
WARNING
• Ground wiring is required to prevent accidental electrical shock during current leakage, communication problems from electrical noise, and
motor current leakage.
• Install a main shutoff switch that interrupts all power sources simultaneously. There is risk of fire, electric shock, explosion, physical injury
or death.
• Communication cable between Master ODU to Slave ODU(s), and Master ODU to IDUs to be 18 AWG, 2-conductor, twisted, stranded,
shielded. Ensure the communication cable shield is properly grounded to the Master ODU chassis only.
communication cable at any other point. Wiring must comply with all applicable local and national codes. Inadequate connections may
generate heat, cause a fire, and physical injury or death.
• The GND terminal at the main PCB is a negative terminal for dry contact, not a ground. Inadequate connections may generate heat, cause
a fire, and physical injury or death.
Heat Pump Operation
Communications Cable Between Master Outdoor Unit and Indoor Unit
Master Outdoor Unit Communication Terminal Block
ODU
B A B
3(A) 4(B)
Indoor Unit
• Make sure that the terminal numbers of master outdoor unit and slave outdoor unit(s) match (A to A, B to B). The system will malfunction if
not properly wired.
• Maintain polarity throughout the communication network. The system will malfunction if not properly wired.
• If the system operates in reversed phase, it may break the compressors and other components.
• If there is a possibility of reversed phase, phase loss, momentary blackout, or the power goes on and off while the system is operating, install
84 | ELECTRICAL CONNECTIONS
R(L1) S(L2) T(L3)
R(L1) S(L2) T(L3)
Switch Switch Switch
Fused
Disconnect
Fused
Disconnect
Disconnect
Power Line
(2-wire Cable)
Power Line
(3-wire Cable)
Pull box Pull box
(Installer option) (Installer
option)
Power Line Power Line
(2-wire Cable) (2-wire Cable)
Communication Line
(3-wire Cable)
IDU CENTRAL DRY1 DRY2 GND 12 V
A B A
4(B)
3(A)
Indoor Unit
©
Master
)
R(L1) S(L2) T(L3
Fused
Pull box
(Installer
option)
Power Line
(2-wire Cable)
Indoor Units
Communications Cable Between Master Outdoor Unit and Slave Outdoor Unit(s)
Master Outdoor Unit Communication Terminal Block
ODU IDU
A
B A B
ODU IDU
A
B A B
ODU IDU
A
B A B
Slave1 Slave2
Communication Line
(2-wire Cable)
Power Line
(2-wire Cable)
Do not ground the ODU to IDUs
CENTRAL DRY1 DRY2 GND 12 V
B A
Slave 1 Outdoor Unit Communication Terminal Block
CENTRAL DRY1 DRY2 GND 12 V
B A
Slave 2 Outdoor Unit Communication Terminal Block
CENTRAL DRY1 DRY2 GND 12 V
B A