Delta-T HH2, User Manual

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SM200 and ThetaProbes Moisture Meter User Manual 4.0
Field Capacity
Sets the Field Capacity, used for mm Deficit calculations.
Options: 0 to 1 Default: 0.38 Units: m
3
.m
-3
If you want mm Deficit you must define the Field Capacity (and Root Depth in the
Options, Data menu). We provide a table for Mineral soils on page 106. Organic
soils are so variable you have to determine field capacity experimentally, before it
makes any sense to take mm Deficit readings - see "Calculating Field Capacity" on
page 108.
Press
Set
to select
Options, Soil Set-Up
menu
.
Scroll through the Soil names, choose one, pressing Set :.
Select Capacity .
Scroll to select the actual field capacity.
Press Set to select it.
Note : A negative "mm Deficit" result indicates you set the Field Capacity too low.
Display Units Options
Selects the units in which new readings are to be displayed and stored.
Option Description
m
3
.m
-3
Volumetric moisture content in cubic metres of
water per cubic metre of soil
%Vol Volumetric water content as a percentage
mm Deficit Soil moisture deficit in mm.
mV Sensor output in milliVolts.
mm Deficit
+ m
3
.m
-3
Soil moisture deficit in mm
Volumetric water content in m
3
.m
-3
.
mm Deficit
+ %vol
Soil moisture deficit in mm
Volumetric water content in m
3
.m
-3
.
m
3
.m
-3
+ mV
Volumetric water content in m
3
.m
-3
Sensor output in milliVolts
%Vol
+ mV
Percentage water content
Sensor output in milliVolts.
mm Deficit
+ mV
Soil moisture deficit in mm
Sensor output in milliVolts.
Warning : Use of the HH2 default value for Field Capacity may not give meaningful
results because it may not represent a common soil type.
Select the Options, Display menu .
Scroll through the following options and press Set to select one.