Figure 38: Examples Of Poor Material Calibration Points - Hydronix Hydro-Probe XT User Manual

Chapter 5
2.5.1 Calibration inaccuracy is likely to result if:
Too small a sample of material is used for measuring the moisture content.
•
A very small number of calibration points are used (in particular 1 or 2 points).
•
The sub-sample tested is not representative of the bulk sample.
•
Samples are taken close to the same moisture content, like the calibration graph
•
shown below (left). A good range is necessary.
There is a large scatter in the readings as shown in the calibration graph below
•
(right). This generally implies an unreliable or inconsistent approach to taking
samples for oven drying or poor sensor positioning with inadequate material flow
over the sensor.
If the averaging facility is not used to ensure representative moisture reading for
•
the entire batch.
Poor Moisture Calibration Data
12
10
8
6
4
2
0
0 20
Sensor Unscaled Output
50 Hydro-Probe XT User Guide HD0538 Rev: 1.6.0
40 60 80

Figure 38: Examples of poor material calibration points

Sensor Integration and Calibration
Poor Moisture Calibration Data
12
10
8
6
4
2
0
100 0 20 40 60 80
Sensor Unscaled Output
100