Control Of Master/Slave Group; Summary Of Control Of Master/Slave Group; Setting Method - Hitachi SAMURAI Series Service Manual

2 Control Functions

Control of Master/Slave group

2.3 Control of Master/Slave group

2.3.1 Summary of control of Master/Slave group

In addition to the operation as a single chiller unit, this product allows the operation of multiple chiller units as a single
heat source system.
1 Features
• The function to control the Master/Slave group comes equipped as standard, and thus an exclusive controller is not
necessary.
• It is possible to connect up to 8 modules to 1 group.
• The modules within 1 group should be set with module number addresses between 1 and 8, and the module
designated as unit 1 controls the number of units
• There is a mode that determines the number of units in operation from the variations in inlet temperature of the chiller
unit (1-pump system).

2.3.2 Setting method

1 For standard specifications (RCME-WH1), the following settings are done locally.
a. Connection of transmission wires
Connect the terminal boards of the chiller units that compose a same chiller group (a maximum of 8 units) with
transmission wires.
b. Setting of terminal resistance
Perform the setting of the terminal resistance. Choose one unit, which may be any from unit 1 to 8, and switch ON
(up) DSW7-1 of its CPU PCB (PCB
c. Setting of address
For all the chiller units in the same group, configure address settings.
Set the addresses in ascending order, without leaving gaps. (Example: Set unit numbers from 1 to 5, if there are 5
units connected).
Missing or duplicated numbers will result in transmission error.

DSW3 of setting PCB (PCB
Unit 1 (Master)
Unit 2 (Slave 1)
Unit 3 (Slave 2)
Unit 4 (Slave 3)
Unit 5 (Slave 4)
Unit 6 (Slave 5)
Unit 7 (Slave 6)
Unit 8 (Slave 7)
d. Setting of number of connected units
For the chiller unit set as unit 1 by address setting, configure the setting of the number of chiller units connected
to the same group. (This setting is not required for units 2 to 8).
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N O T E
• Refer to the instructions for water piping works for the attachment position of each sensor.
• Plug in the connector of each sensor into the control PCB of the chiller unit set as unit 1 by address settings.
40 SMGB0120 rev.0 - 11/2017
).
C
)
A
#1
OFF OFF
OFF OFF
OFF ON
OFF ON
ON OFF
ON OFF
ON ON
ON ON
PCB Unit 1 only
A
RSW1
#2 #3
OFF
ON
OFF
ON
OFF
ON
OFF
ON
Adjust the arrow
to the number
#4
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF