In-Situ RDO PRO Process Optical Dissolved Oxygen Sensor Manual - Manual (Page 11)

5.0 Controller Requirements and Connections
The RDO PRO Probe may be connected to a controller or logger for communication via:
• Analog (4-20 mA) provides a configurable 4-20 mA current loop output
• SDI-12
• RS485 Modbus
• RS232 Modbus
5.1 Wiring Overview
Refer to diagrams on the following pages. Trim and insulate unused wires. The shielded wire should
be wired to a chassis ground or earth ground.
Signal Color
Ground/Return Black
External Power Red
4-20 mA Brown
RS485 (-) Green
RS485 (+) Blue
SDI-12 White
The inside of the controller must be kept free of moisture and humidity. Condensed
moisture can migrate through the wiring and cause the probe to fail. Therefore,
desiccant should be installed in the controller and be replaced on a regular basis.
Page 11 Controller Requirements and Connections