
Version 2.12
©Copyright 2020, Ambient LLC. All Rights Reserved.
Page 44
Select field
Scroll field up Scroll field down
return to Setup
Figure 43
6.7.19
Soil Moisture Calibration
The soil moisture sensor provides for optional two-point linear calibration. This is important due to
different soil types and density.
The calibration equation is defined as:
% Soil Moisture (calibrated) = (Now AD – 0%AD) *100 / (100%AD – 0%AD)
Where AD stands for “analog to digital” and is the unscaled digital value, Now AD is the currently
measured AD and the other parameters are described below.
6.7.19.1
0% Soil Moisture Set Point
To determine the 0% soil moisture, collect a soil sample in a cup from where the sensor will be
installed, and allow the soil to completely dry out. Next, place the soil sensor in the medium and allow
the sensor to stabilize for one hour.
Next, set the
0%AD
calibration set point to the
Now AD
value.
6.7.19.2
100% Soil Moisture Set Point
To determine the 100% soil moisture, collect a soil sample in a cup from where the sensor will be
installed, and add water and mix until the soil is saturated, and there is no standing water. Next,