D
However, the user can also choose to take into account the length of the column of water in each
tensiometer, by adding this into the offset count. This static pressure of water is more significant
with longer tensiometer lengths. Please see the SKT 600 Series Tensiometer manual for a full
explanation of this, and a table of pressures equivalent to tensiometer lengths.
e.g. for a tensiometer with 600 mm acrylic shaft length, static pressure of water column is
61.5 hPa (sensitivity 1 mV per 20 hPa)
From the sensor sensitivity, 61.5 / 20 = 3.075 mV
So an additional offset count of 3.075 mV must be taken into account
Additional offset count = 3.075 * 10 * 9.5 = 292.1
Hence new offset count = 285.1 + (-19) = 273.1
ENTER as +0273
NOTE : When a tensiometer is supplied together with a DataHog logger directly from Skye
Instruments, the shaft length and static water pressure is calculated and entered into the offset
count ready for use. See the Hardware Configuration Certificate in the DataHog manual, which
specifies which tensiometer is for use with which channel.
However, if the tensiometer is to be used horizontally or non-vertically, the user will need to
recalculate and re-enter the sensor offset as appropriate.
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