Dynamax HPFM3, Installation And Operation Manual, Page: 56 / 86

Revision: JUNE 2017 56
7.3 Raw data tables, project data
Users who want to make temperature corrections should measure the temperature dependence of their study species for
the sake of maximum accuracy. Fortunately, in many cases the two temperature corrections cancel out if the following
conditions hold: (1) The temperature dependence of the capillary tubes on the HPFM and of the sample are equal. (2) The
HPFM and the sample are at the equal
temperature, even though the temperatures might differ between measurements.
7.4 K25 - Conductance At Standard Temperature
In the case of temperature differences between samples taken, one may want to make an additional correction. For those
cases where many different plants were measured at many different temperatures we suggest converting to a standard
temperature for a direct comparison or for publications. With HPFM Gen 3, the software computes the K25, the corrected
conductance, adjusted again from the reading temperature to an equivalent conductance at 25
o
C.
The temperature correction is approximately 2.4%/
o
C so if measurements are made over a range of 15 to 35
o
C, stem
conductances can change by 48%.
Below is the example of the transient measurement results. Each time the user performs a regression, the K, Kcorrected,
and K25 are added to the data files as shown below.