Brix Calibration - Hydronix Hydro-Probe Configuration And Calibration Manual

Chapter 3
9. The calibration data can be entered into Hydro-Com or excel to calculate the calibration
coefficients. This can also be done manually using the following equations:
B (Gradient) =
5.96−4.36
46−35
B =
1.6
11
B=
Moisture % = �� �� ���������������� + ��
B = 0.145
∴
C (offset) = ����������������% − ( �� �� ���������������� )
C = 5.96 − ( 0.145 �� 46 )
Using the wet mix values:
C = 5.96 − 6.67
C = -0.71
10. If the B and C values are loaded into the sensor the output can be configured to
Moisture%.
Moisture % = 0.145 �� 58 − 0.71
Using the B and C values in this example if the Unscaled value is 58:
Moisture % = 7.7%
As long as the recipe and material proportioning remain the same the calibration will be valid.

9 Brix Calibration

Selected sensors have the ability to derive the Brix content of a liquid from the Unscaled value
(See the Technical Specification in the individual Sensor Installation Guide for more information).
This is a measure of the amount of dissolved solids present in a liquid and is mainly used in the
food industry.
The Brix calculation is different from the linear calculation used for moisture. To create a
calibration line the following equation is used:
where 'us' is the Unscaled value from the sensor. This equation gives an exponential curve.
When using the sensors to measure Brix, the sensor must still be calibrated to the process being
monitored. The process is detailed below;
1. To calibrate the sensor, a number of Unscaled values need to be correlated to their
corresponding Brix value.
2. To perform the calibration the Filtered Unscaled value is recorded and at the same time a
sample of the material is collected. This sample should be taken as close to the sensor
as possible. This will ensure that the material collected is a true representation of what
the sensor was measuring.
3. When a calibration sample is required ensure the material is flowing in the process.
Record the Filtered Unscaled value from the sensor and at the same time collect the
material sample using an appropriate sampling method.
4. The sample should be large enough to enable several laboratory tests to be performed.
The results from the laboratory should be compared as variations in the results will
indicate errors in the sampling or the laboratory process.
38 Configuration and Calibration Guide HD0679 Rev 1.2.0
���������������� ( ������ ) −����������������(������)
���������������� ( ������ ) −����������������(������)
= −
Brix A B
Sensor Integration and Material Calibration
⋅
⋅ + ⋅
( C us )
e D us ²