Hydronix HV04, Руководство пользователя

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Hydro-View User Guide HD0531 Rev 2.0.0 67
Chapter 6 Material Calibration
1 Introduction to Calibration
For sensor applications where the moisture % is required to be directly output, the sensor will
require calibrating to the material that is to be measured.
The Hydro-View calibration facility is used to capture Unscaled values and to compare this
against corresponding moisture values derived from taking and drying samples. This utility is
intended for use with sensors measuring in flowing materials, such as in bins or on conveyor
belts. The calibration procedure for mixer applications where water is added under controlled
conditions to reach a specified moisture value is performed by the mixer control system or a
Hydro-Control and not by the Hydro-View.
For full details about the calibration process see the Configuration and Calibration
guide HD0679 or the specific sensor user guide.
2 Calibrating a Sensor
2.1
Coefficients
The calibration process is performed to enable the coefficients to be calculated that are
required to convert the sensors Unscaled output into a true moisture %. For most applications
only the B and C coefficients are required, see the Configuration and Calibration guide
HD0679 for details.
All of the latest Hydronix Moisture Sensors (excluding the Hydro-Probe) have the ability to
select the Measurement Mode used to calculate the Unscaled output. To output moisture
using the different Measurement Modes requires separate coefficients for each mode (F, E
and V).
In older Hydronix sensors (Pre Firmware HS0102) the sensor has to be calibrated
separately in each Measurement Mode to create the coefficients.
When the Hydro-View is connected to the latest versions of the sensors (Firmware HS0102 or
higher) the Unscaled values for each Measurement Mode are stored at the same time. This
facility gives the user the ability to calculate the coefficients in each Measurement Mode
simultaneously. With all Measurement Modes calibrated it is possible to select the most
appropriate Measurement Mode to use for a given material without requiring the calibration
process to be re-done. The sensor stores the coefficients internally for each Measurement
Mode enabling the sensor to output the Moisture % for any Measurement Mode as required.
2.2
Calibration Data Table
All calibration data points, including the Unscaled values for each Measurement Mode and the
resultant moisture %, are stored in the sensors memory (Only available with sensors with
firmware HS0102 or higher). This enables the user to interrogate the values used to create
the coefficients and the moisture spread of the collected samples. The chart will also indicate
which samples have been included in the calculations.
Figure 64: Calibration Data Table