Hitachi UTOPIA RASC Series Installation And Operation Manual page 39

ELECTRICAL WIRING
13.3. COMMON WIRING
13.3.1. ELECTRICAL WIRING BETWEEN INDOOR UNIT
AND RASC UNIT
Connect the electrical wires between the indoor unit and the
RASC unit, as shown below.
Check to ensure that the terminal for power source wiring
(terminals "L1" to "L1" and "N" to "N" of each terminal board:
AC230V), and intermediate wires (Operating Line: terminals "1"
to "1" and "2" to "2" of each terminal board: DC5V) between the
indoor unit and the RASC unit coincide correctly. If not, some
component will be damaged.
Follow local codes and regulations when performing electrical
−
wiring.
Connect the operation wiring to the units in the same
−
refrigerant cycle (The refrigerant piping and the control
wiring should be connected to the same indoor units). If
the refrigerant piping ant the control wiring are connected
to the units in the different refrigerant cycle, it may cause a
abnormal operation.Use twist pair wire (more than 0.75 mm²)
for operation wiring between RASC unit and indoor unit, and
operation wiring between indoor units (H-Link connection).
It can be also used shielded pair wiring. Shield shall be
connected to earth only in one cable side.
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.
RASC-(3/5)HVRNE
¡
Power source from the RASC unit to the indoor unit
Terminal board
Circuit breaker
Earth leakage breaker
Field wiring
Field-supplied
Optional accessory
RASC-10HRNE
¡
Power source from the RASC unit to the indoor unit
Terminal board
Circuit breaker
Earth leakage breaker
Field wiring
Field-supplied
Optional accessory
RASC unit
of system no. 0
Operating line
(twisted shielded pair cable
or shielded pair cable)
DC5V (non-pole transmission,
H-LINK system)
Indoor unit Indoor unit
Remote
control
switch
In RASC-3/5HVRNE: Max. 2 indoor units for refrigerant cycle
RASC unit
of system no. 0
3 N
Operating line
(twisted shielded pair cable
or shielded pair cable)
DC5V (non-pole transmission,
H-LINK system)
Indoor unit Indoor unit
Remote
control
switch
Max. 4 indoor units for refrigerant cycle
Do not use more than 3 cores for operation wiring (H-Link).
−
Core sizes must be selected according to the national
regulations.
Open a hole near the connection hole of power source wiring
−
when multiple RASC units are connected from one power
source line.
The recommended breaker sizes are shown in Table of
−
electrical data and recommended Wiring, Breaker Size/1
O.U.
In the case that a conduit tube for field-wiring is not used, fix
−
rubber bushes with adhesive on the panel.
All the field wiring and equipment must comply with local and
−
international codes.

CAUTION:
All the field wiring and electrical components must comply
with local codes.

ATTENTION:
Pay attention to the connection of the operating line. Incor-
rect connection may cause the failure of PCB.
Independent power source of RASC unit and indoor unit
RASC unit
of system no. 0
Indoor unit
In RASC-3/5HVRNE: Max. 2 indoor units for refrigerant cycle
Independent power source of RASC unit and indoor unit
RASC unit
of system no. 0
3 N
Indoor unit
Max. 4 indoor units for refrigerant cycle
PMML0140A rev.1 - 07/2009
Operating line (twisted
shielded pair cable or
shielded pair cable)
DC5V (non-pole
transmission,
H-Link system).
Indoor unit
Remote
control
switch
Operating line (twisted
shielded pair cable or
shielded pair cable)
DC5V (non-pole
transmission,
H-Link system).
Indoor unit
Remote
control
switch
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