Delta-T HH2, User Manual

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Equitensiometers
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Equitensiometers
Contents:
About Equitensiometers
Navigation Map
Options
EQ2 Options Summary
Reading the Equitensiometer
About Equitensiometers
Equitensiometer type EQ2 measures the negative pressure (or suction) required to
extract water from between the matrix of soil particles. This is an important indication
of plant water stress. See also the Glossary.
Equitensiometer readings are normally given in kPa, but the HH2 only displays the
output in mV. Once readings are uploaded to your PC you may derive the soil matric
potential (in kPa) using the unique linearisation table supplied with each sensor, as
described in its User Manual.
When the Moisture Meter wants a reading it applies an excitation voltage for as long
as it is needed. The excitation voltage, taken from the meter’s internal battery,
stimulates the Equitensiometer into taking a reading and producing an output signal in
mV.