APC NBRK0200 configurationmanual How to Wire to the Modbus Interface

How to Wire to the Modbus Interface

To connect to your building management system, use the Modbus RS-485 interface. The Modbus interface supports 2-wire RS-485, plus ground. In addition, Modbus requires both termination and polarization resistors at the bus master. Each end of the bus requires a 150-ohm resistor (provided), and the bus also requires a 400–650-ohm resistor (provided) from D1 to +5 Vdc and from D0 to GND. Modbus can be configured to communicate at either 9600 or 19200 bps. The default setting is 9600 bps.

For more information, see the Modbus standard available at www.modbus.org.

NetBotz Rack Monitor 200 Installation and Quick Configuration Manual 13