Sutron Corporation Satlink Operations & Maintenance Manual, Rev 8.04.2 11/3/2016 pg. 23
4.8.
Connecting RS485 Sensors
SL3 supports RS485 sensors that use the SDI-12 protocol for its messaging. SL3 will not be able to
read data from RS485 sensors that do not support SDI-12.
The typical connection of the RS485 sensor is shown below:
4.9.
Connecting Tipping Bucket Rain Gauge
SL3-1 supports a tipping bucket rain gauge using its TB/DIN2 connection. This connection
provides a pullup resistor (100K) to 3.3V to provide power for the contact switch in the rain
gauge. Each time the bucket in the rain gauge “tips” the internal switch closes momentarily
causing a pulse on the TB/DIN2 connection. This pulse is counted and used to provide
accumulated precipitation or precipitation rate data.
The key settings for a tipping bucker rain gauge are:
Measurement Type: Precip Accumulation or Precip Rate
Slope: 0.1mm, 0.2mm, 0.01inches or other value to match the calibration of the sensor.
Note: Measurement type: digital/counter1 or counter2 can also be used for tipping bucket rain
gauges. Be sure to select “debounce” for this measurement type as most tipping bucket rain
gauge switches are noisy and can produce multiple counts per tip if they are not de-bounced.
The typical connection of the tipping bucket rain gauge is shown below.