9.2
Connecting the controller in a building
management system via a Modbus protocol
1. Termination is only done for the last
unit.
9.3
Control modes through the bus
Various control modes can be set for the controller through the bus (Holding
Register 4x00001). For more information, see
Section 11.1 Modbus registers
•
Away
: The controller monitors an expanded dead zone in the
Away
mode.
This helps to save energy. The dead zone can be adjusted via the bus by
using a parameter (Holding Register 4x00202) or via the controller’s settings
menu.
•
Flush
: Cooling and heating controls are in full operation (100%) in the
Flush
mode. The
Flush
mode can be activated via the bus by using a parameter.
•
Test mode
: The
Test mode
has to be activated if commissioning is
performed remotely. The
Test mode
allows controlling the fan and the
cooling and heating valves by using parameters.
9.4
Alarms received through the bus
The controller can send indicative alarm signals also through the bus. These
alarm signals do not affect the controller operation but do indicate a failure
detected in the system.
•
Temperature sensor alarm
: The temperature sensor alarm indicates a
failure in the incoming or outgoing water temperature sensor.
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VariPro Room controller – Installation and Operation Manual
