Hydronix Hydro-Mix, Configuration And Calibration Manual

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Sensor Integration and Material Calibration Chapter 3
Configuration and Calibration Guide HD0679 Rev 1.2.0 33
5.1
Hints and Safety
•
Wear safety glasses and protective clothing to guard against expulsion of material during
the drying process.
•
Do not attempt to calibrate the sensor by packing material on the face. The readings
obtained will not be representative of those from a real application.
•
Whilst recording the sensor Unscaled output, always sample where the sensor is located.
•
Never assume that material flowing out of two gates in the same bin is the same moisture
content and do not attempt to take samples from the flow in both gates to get an average
value – always use two sensors.
•
Where possible, average the sensor’s readings either in the sensor using the digital input,
or inside the control system.
•
Ensure the sensor sees a representative sample of material.
•
Ensure a representative sample of material is taken for moisture testing.
5.2
Equipment
•
Weighing scales – to weigh up to 2kg, accurate to 0.1g
•
Heat source – for drying samples, such as an oven, microwave or moisture balance.
•
Container – with re-sealable lid for storing samples
•
Polythene bags – for storing samples prior to drying
•
Scoop – for collecting samples
•
Safety equipment – including glasses, heat resistant gloves and protective clothing.
NOTES: For full instructions on using Hydro-Com, refer to the Hydro-Com User Guide
(HD0682). Record all calibration data including suspected erroneous results.
The same principles apply with or without using Hydro-Com when calibrating.
5.3
Procedure
1. To perform the calibration it is essential that the averaged Unscaled value is recorded as
the material is passing the sensor. At the same time a sample of the material needs to be
collected. Samples should be taken as close to the sensor as possible this will ensure
that the sample collected is a true representation of the material the sensor was
measuring.
2. To perform the calibration the Average Unscaled value can be obtained by either
triggering the Average/Hold input by applying 24v to the digital input or manually
selecting start averaging using Hydro-Com. The optimum installation is one where the
digital input is wired into the control system. When the bin opens, the Averaging will start
and when closed the averaging will stop, the value will be held until the averaging is
started again. Averaging must be triggered by the main dose of material, any jogging of
material should not activate the sensor digital input.
3. Once the material has started to flow consistently the averaging should start. Collect at
least 10 sample increments from the flow to yield a bulk sample of at least 5kg
1
of
material in the container. The material MUST be collected at a position close to the
sensor so that the sensor reading relates to the particular batch of material that has been
collected.
4. Stop the material flow. Record the Average Unscaled value from the sensor.
5. Thoroughly mix the collected sample to create a homogenous mix. This sample should
be sealed in an air tight bag and kept out of the sun until it is ready to be analysed. It is
very important that the moisture in the sample is not allowed to escape.
6. Take 3x1kg samples of the material collected and perform a laboratory test on each.
Ensure all moisture is removed. Some materials, such as Grain, will require grinding
before drying, see the appropriate industrial standards for the material for more details.