Alfa Laval AquaFirst
Installation, service and operating instruction
38
12
Modbus
12.1 Modbus communication
The controller includes a Modbus slave communication protocol, type
Modbus RTU RS485.
Connection between BMS (building management system) and Micro 3000
requires two polarized wires on C+ and C-, respectively labelled 25 and 26
on controller C Bus terminal.
The connection via shielded cable is not required but can be performed
with the terminal 24. For this, it is necessary to unscrew the front panel.
Picture 21
Picture 22
12.2 Connecting multiple Micro 3000 control boxes
Rules to respect
Max length between BMS and farer control box: 500 meters
Connection continuity (C+ and C-) has to be done directly on the controller C Bus terminal,
without using derivation boxes. Respecting this, there are two wires per terminal, except the farer
control box.
Picture 23
