Chapter 5 Sensor Integration And Calibration; Sensor Integration; Sensor Calibration; Figure 34: Calibrations For Two Different Materials - Hydronix Hydro-Probe XT User Manual

Chapter 5

1 Sensor Integration

The sensor may be integrated into a process in one of three ways:-
The sensor may be configured to output a linear value of between 0-100 Unscaled units
•
with a material calibration being performed in an external control system.
Or
• The sensor may be internally calibrated using the Hydro-Com sensor configuration and
calibration software to output an absolute moisture percentage value.
Or
The sensor could also be used as a target value
•
RS485 development tools are available from Hydronix for system designers who wish to develop
their own interface.

2 Sensor Calibration

Introduction to material calibration
2.1
The raw output of a Hydronix sensor is an Unscaled value ranging from 0 to 100 units. Each
sensor is set so that a 0 Unscaled value relates to the measurement in air and 100 relates to
water.
The relationship between the change in moisture % to the change in Unscaled value will not
be the same for two different materials as shown in Figure 34. This is because each material
has its own unique electrical characteristics. Calibration is the process of mapping the
sensors Unscaled readings to a value that represents the material moisture percentage.
20%
0
C
Sensor unscaled reading

Figure 34: Calibrations for two different materials

Sensor Integration and Calibration
Material 2
Material 1
Calibration Line
B
Moisture %
B=
Unscaled Value
100
Hydro-Probe XT User Guide HD0538 Rev: 1.6.0 43