Appendix a networking, Connecting several wxt520s on the same bus, Sdi-12 serial interface – Vaisala WXT520 User Manual
Page 151: Wiring, Appendix a, Networking, Sdi-12 serial interface wiring
Appendix A ______________________________________________________________ Networking
VAISALA______________________________________________________________________ 149
APPENDIX A
NETWORKING
Connecting Several WXT520s on the Same Bus
Connecting several WXT520s on the same bus is possible in two ways:
1.
Using SDI-12 serial interface and communication protocol, and
2.
Using RS-485 serial interface and one of the following
communication protocols: ASCII or NMEA 0183 v3.0.
SDI-12 Serial Interface
Wiring
1.
Make the SDI-12 wiring in WXT520 as described in
Wiring and Power Management, on page 43
. Remember to
combine the two "Data in/out"wires of each WXT520 either in the
internal screw terminal inside or outside the transmitter.
2.
In the data logger end, combine the "GND for data" wires of each
WXT520 to the logger "GND for data" wire. Connect the "Data in/
out" wires of each WXT520 to the logger "Data" wire.