12 - OPTIONS
12.2.4 - Two units running as master/slave
The customer must connect both units with a communication
bus using a 0.75 mm² twisted, shielded cable (contact the
manufacturer's Service for installation).
All parameters required for Master/Slave operation must be
configured by the Service configuration menu.
All remote controls of the Master/slave assembly (start/stop,
unloading, etc.) are managed by the unit configured as Master
and must be applied only to the Master unit.
Units supplied with hydronic module
Master-slave operation is possible only when the units are
installed in parallel:
-
The master-slave assembly is controlled on the water inlet
without any additional sensors (standard configuration) (see
example 1).
-
Control of Master and Slave on the water outlet is possible
by adding two additional sensors in the common supply pipe
work (see example 2).
Each unit controls its own water pump.
Units supplied without hydronic module
In the case of units installed in parallel and if there is only one
common pump installed by the installer, isolating valves must be
installed on each unit. These should be controlled (opened and
closed) using the control for the relevant unit (valves for each
unit can be controlled using the unit water pump control outputs).
Refer to the control manual for the connections.
The control of a variable speed pump must be, in this case,
carried out by the unit via the 0-10 V dedicated output of the
Master unit (control on Delta T° only).
An installation in series is only possible with a fixed speed pump
(example 3):
-
The operation of the pump will be controlled by the Master
unit.
-
The Master-Slave assembly is controlled on the water outlet
without additional sensor.
-
The installation must be carried out only according to the
diagram given in the example 3.
IMPORTANT:
Both of the units must be equipped with an option to allow Master-
Slave operation.
If one or both units is equipped with the variable speed pump
option, it is strongly recommended not to set the control mode
on the pressure differential.
The same setpoint is recommended for configuring the
temperature differential mode.
Case 1: operation in parallel - control on water inlet
for units with hydronic modules
Case 2: operation in parallel - control on water
outlet for units with hydronic modules
Case 3: operation in series - control on water outlet
for a combination of units
Legend
B
Master Unit
C
Slave unit
Electrical boxes for Master and Slave units
Water inlet
Water outlet
Water pumps for each unit (included as standard in units with hydronic
module)
T
Additional sensors for the control of the water outlet to be connected
on channel 1 of the slave boards of each Master and Slave unit
Communication bus CCN
Connection of two additional sensors
Non-return valve
AQUACIAT
POWER
ILD
EN-58
