This post documents how to wire and connect to the YSI EXO3s Multi-parameter Sonde. A note about EXO3s - it is the same as EXO3 but without a battery pack inside the housing.
Materials
- YSI EXO3s Multi-parameter Sonde
- SDI-12 to USB adapter
- 12V power supply like this one
- Sub connector cable with 6 conductors
- Micro USB cable
Sensor Pinout and cable
For this section, I want to wire the SDI-12 lines from the sensor to an SDI-12 to USB adapter to make sure we have the pinout and wring right, and the sensor shows up as a USB port.
Based on the EXO3’s manual page 30, the wiring for native SDI-12 communication is GND on black and bare wire, Data on orange wire, 12VDC on red wire.
Unfortunately, I don’t have the flying lead cable that is mentioned in the manual. We have a similar “subconnector” cable available but the cable colors are most likely not the same as the flying lead cable.
To use this cable, I need the pinout of the of the male connector on the sensor side. The YSI support team provided us with the pinout details -
After using a multimeter and checking which color of the subconn conductor is which pin, I figured out which color of the subconn cable wires is which SDI-12 net. Here below:
| net name | pin | cable color (flying lead) | cable color (subconn) |
|---|---|---|---|
| SDI12 Data | 1 | orange | black |
| GND | 2 & 4 | black, bare | white, green |
| 12V | 3 | red | red |
Wiring
