In-Situ RDO PRO Process Optical Dissolved Oxygen Sensor Manual - Manual (Page 12)

5.2 Analog (4-20 mA) 3-wire
Signal Color
Ground/Return Black
External Power (12-36 VDC) Red
4-20 mA Brown
 Cable length must not exceed 1219 m (4000 ft.)
 Analog signal must be enabled in Win-Situ ® 5 Software or the Comm Kit Software
prior to use.
Page 12 Controller Requirements and Connections