29
10.4 Test Instrument integrity prior to deployment in the field
11 Corrections
The correction parameters are used when the SFM1 Sap Flow Meter is used to
process data on board without the aid of Sap Flow Tool software.
11.1
Probe Spacing
Probe spacing must be set to the distance between the needles as they were
installed in the stem as this parameter is used in the HRM Algorithm.
•
Where:
•
k is the thermal diffusivity of wet wood
•
x is the distance between the heat source (heater) and temperature
sensors
•
v1 and v2 are the increases in temperature (from ambient) at equidistant
points downstream and upstream from the heater
ICT International
Enabling better global research outcomes in soil,
plant & environmental monitoring.
A
manual measurement
option
is also available which is convenient for
testing instrument operation and integrity of the needles prior to field
deployment. Use the HRM-TB Test Block to confirm the integrity of the needles
and the instrument prior to deployment in the field. The Test Block has been
engineered to produce a known set sap velocity when a manual measurement
is made.
If the instrument does not return a sap velocity within the range 14 to 18 cm
/
hr
please contact
us
via our website RMA
form
:
http://ictinternational.com/support/rma-form/
T
his test provides confidence that the instrument is fully functional before leaving
for a
fieldsite.
