In-Situ Aqua TROLL 400 Operators Manual - Manual (Page 32)

800-446-1500 32 www.in-situ.com
Controller Requirements and Connections
The instrument can be connected to a controller or logger for communication via the
following protocols.
l
SDI-12
l
RS485 Modbus
l
RS232 Modbus (with converter)
Wiring Overview
Refer to the diagrams on the following pages. Trim and insulate unused wires. The
shielded wire should be wired to a chassis ground or earth ground. See "Safety" on
page 5.
Stripped-and-Tinned Cable
Signal Color
Ground/Return Black
External Power Red
No Connection Brown
RS485 (-) Green
RS485 (+) Blue
SDI-12 White
Power Connections
The Aqua TROLL 400 requires an external 8 to 36 VDC power source. The red wire
must be connected to the positive terminal of the power source. The black wire must be
connected to the negative terminal of the power source, which is often referred to as the
system ground or return.