Carrier RTU OPEN 11-808-427-01 - Manual (Page 15)

RTU Open 9
Optional
* Safety chain devices, field-installed - normally closed. Apply 24 Vac to this terminal
(jumper from J1 - 1 to J1 - 9) where no safety devices are installed.
** Fire shutdown device, field-installed, configurable as normally open or closed
*** Enthalpy switch, field-installed - configurable as normally open or closed
To set the RTU Open's address
The RTU Open's two rotary switches determine the RTU Open's MAC address when it is placed on an MS/TP
network. The rotary switches define the MAC address portion of the RTU Open's BACnet device instance
number, which is composed of the MS/TP network number and the MAC address. They also set the slave
address on a Modbus or N2 network when less than 100. See the RTU Open Integration Guide for additional
information on integration.
CAUTION
The MAC address of the controller must be unique on its network.