Delta-T Devices DL6, Руководство пользователя

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Channel Properties
Each row of the Program tab in the DL6 Control Panel lists the channel
properties, these define how raw data from a sensor is to be converted into
engineering units.
In Program tab, if necessary, click on Change to enable program editing.
Double click on any of channels 1 to 6 to display the Soil Moisture
(Voltage) Channel Properties dialog.
This example shows the channel properties for a PR1/4 Probe.
Soil Properties : Two linear
coefficients a0 and a1 are used
to convert measured soil
permittivity* into moisture
content. This conversion
depends on the soil type.
Two standard Soil Types are
provided: Mineral or Organic
soils.
*Footnote: Our soil moisture sensors
actually measure the
square root of
permittivity, converting that to
moisture by the use of these two
coefficients.
About a0 and a1.
These parameters are used with the selected sensor-specific Linearisation
Table in the DL6, to convert the sensor mV output into soil moisture
readings. They are a convenient and efficient way of describing the
calibration curves for different soil types without the memory overhead
required for a unique table for every different soil.
For optimum accuracy you should obtain soil-specific calibration coefficients
for your soil as described in your sensor user manual.
You may skip this step by choosing the Mineral or Organic Soil Types. You
lose some accuracy but it is easier. Their soil coefficients are permanently
installed in the DL6.
Data storage- Maximum, Minimum and Resolution.
These can be used to scale charts, select a suitable number of decimal
places, and control the amount of memory used. The default values are
optimised for the standard sensors.
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Software DL6 User Manual v 1.3