Electrical wiring
16.3 COMMON WIRING
16.3.1  Electrical wiring between indoor unit and 
outdoor unit
•  Connect the electrical wires between the indoor unit and the 
outdoor unit, as shown below.
•  If the refrigerant piping and the control wiring are connected to 
the units in the same refrigerant cycle.
•  Use twist pair wire (more than 0.75 mm²) for operation wiring 
between  outdoor  unit  and  indoor  unit,  and  operation  wiring 
between indoor unit and indoor unit.
•  Use 2-core wire for the operating line (Do not use wire with 
more than 3 cores).Use shielded wires for intermediate wiring 
to protect the units from noise obstacle at length of less than 
300 m and size complied with local code.
•  Open a hole near the connection hole of power source wiring 
when multiple outdoor  units  are  connected  from  one  power 
source line.
•  The recommended breaker sizes are detailed in the Wire size 
section.
•  In the case that a conduit tube for eld-wiring is not used, x 
rubber bushes with adhesive on the panel.
•  H-LINK  twist  pair  shielded  cable  must  be  grounded  in  the 
outdoor unit side.
  CAUTION
Pay attention to the connection of the operating line. Incorrect 
connection may cause the failure of PCB. 
All the eld  wiring and electrical components must comply with 
local codes.
16
Power source from the outdoor IVX unit to the indoor unit 
(example)
Independent power source of outdoor IVX unit and indoor unit 
(example)
No.  0  System 
Outdoor unit
No.  0  System
 
Outdoor unit
Operating Line 
(Shielded Pair Cable)
DC5V (Non-Pole Transmission,
 
H-LINK System)
Remote Control Switch 
(Twisted Shielded Pair 
Cable)
Operating Line 
(Twisted Shielded 
Pair Cable)
DC5V (Non-Pole 
Transmission, H-LINK 
System)
Indoor Unit
Indoor Unit
Terminal board
Circuit Breaker
Earthleakage Breaker
Field Wiring
Field supplied
Optional Accessory
Remote Control Switch 
(Twisted  Shielded  Pair 
Cable)
Indoor Unit
Indoor Unit
12
ON
DSW6
12
ON
DSW6
12
ON
DSW6
Operating line
Operating line Operating line
Remote control 
 line
Remote control 
 line
Remote control 
 line
Individual control 
Running ON/OFF individually 
Thermo.ON/OFF individually
Individual control 
Running ON/OFF simultaneously 
Thermo.ON/OFF individually
Simultaneous control 
Running ON/OFF simultaneously 
Thermo.ON/OFF simultaneously
 (IVX series only)