Hitachi PC-ARF Technical Catalogue page 392

5 Centralised remote controls
PSC-A64S
The central control unit is designed to control up to 16 groups of up to 16 units (the maximum number of indoor units is
defined by the H-Link limit).
Each of these groups is made up of two types of unit:
• Master Unit: Unit selected in each group to control and set each of the group parameters equally and at the same
time.
• Slave Unit: Units (up to 15 in one group) which follow the master unit configuration assigned for this group.
To use the central control unit correctly, each group of units must be configured as indicated below:
C A U T I O N
• Before installing the wiring, switch off the power supply to the air conditioning system and central control unit.
• Installing the wiring while the central control power supply is switched on may cause the central control unit to malfunction.
Examples of groups
IU
1 group

Automatic initial group configuration
After completion of electrical wiring work and test running of the air conditioner, turn ON the power supply of the central
station. (Ensure to perform the test runing of the air conditioner before turning ON the power supply of the central sta-
tion).
In case that group setting is not performed, the indication of the central station is as shown below for checking indoor unit
connection after turning ON the power supply.
Refrigerant
Number of checked
cycle on con-
indoor units connect-
nection check
ed in refrigerant cycle
on connection check
N O T E
• The checked number of connected indoor units may be more than the actual number according to the condition of transmission. After
the connection check, the indications of "GROUP" and "SET TEMP."
• During the connection check, the indications of group No. and setting temperature may be "- -" temporarily.
• When the "63" alarm is indicated, the setting of H-LINKII adaptive is wrong. Check for the setting of the central station and other central
controller used together.
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TCGB0106 rev.0 - 12/2014
Master Slave
IU IU
1 group
Completion of
connection check
In case of less than 16 indoor
units connected.
(Set automatically as of zone 1)
IU
1 group
1 group
In case of more than 17 indoor
units connected.
IU