In-Situ Aqua TROLL 400 Modbus and SDI-12 Reference Guide - Manual (Page 8)

1.4 Modbus Master RS485 Wiring Diagram
Cable length must not exceed 1219.2 m (4000 ft).
Signal Color
Ground/Return Black
External Power (12-36 VDC) Red
RS485 (-) Green
RS485 (+) Blue
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