Hydronix Hydro-Mix, Configuration And Calibration Manual

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Chapter 1 Introduction
12 Configuration and Calibration Guide HD0679 Rev 1.2.0
Hydronix Microwave Moisture sensors use high speed digital signal processing filters and
advanced measurement techniques. This gives a signal which is linear with the change in
moisture in the material being measured. The sensor must be installed into a material flow and
will then give an online output of the moisture change in the material.
Typical applications include moisture measurement in Sand, Aggregates, Concrete, Biomass
materials, Grain, Animal feed and Agricultural materials.
The sensors are designed to operate in various applications and have been created to allow the
material to flow past the sensor. The following are examples of typical applications.
•
Bins / Hoppers / Silos
•
Conveyors
•
Vibratory Feeders
•
Mixers
The sensor has two analogue outputs which are fully configurable and can be internally
calibrated to give a direct moisture output which is compatible with any control system.
Two digital inputs are available which can control the internal averaging function. This allows the
sensor measurement, which is taken at 25 times per second, to enable rapid detection of any
changes in moisture content to be averaged. This facilitates easier use in the control system.
One of the digital inputs can be configured to provide a digital output which can provide an alarm
signal in the event of a low or high reading. This can be used to signal a high moisture alarm or
alternatively to signal an operator that a storage bin needs to be refilled.
Hydronix sensors are specially designed using suitable materials to provide many years of
reliable service even in the most arduous conditions. However, as with other sensitive electronic
devices, care should be taken not to subject the sensor to unnecessary impact damage.
Particular care should be paid to the ceramic faceplate which, whilst being extremely resistant to
abrasion, is brittle and may be damaged if hit directly.
CAUTION – NEVER HIT THE CERAMIC
Care should be taken to ensure that the sensor has been correctly installed
and in such a manner to ensure representative sampling of the material
concerned. It is essential that the sensor is installed in a location where the
ceramic faceplate is fully inserted into the main flow of the material. It must not
be installed in motionless material nor where material can build-up on the
sensor.
All Hydronix sensors are pre-calibrated in the factory so that they read 0 when in air and 100
when submerged in water. This is called the ‘Unscaled Reading’ and is the base value used
when calibrating a sensor to the material being measured. This standardises each sensor, so if
a sensor is changed then there is no need to redo the material calibration.
After installation the sensor should be calibrated to the material (see Chapter 3 for more details).
The sensor can be setup in two ways:
•
Calibration inside sensor: Sensor is calibrated internally and outputs true moisture.
•
Calibration inside control system : Sensor outputs an unscaled reading which is
proportional to moisture. Calibration data inside the control system converts this to true
moisture