PASI GEA RM1 1.0, User Manual

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GEA RM1 43
Description of the systems interface in standalone mode
Simplified display of geometric measurement data
The geometric position data of the electrodes in the different measurements are kept
inside the file in the mode called "Integral", ie with the positions of the different electrodes
maintained in the most flexible and complete way possible. In this mode, the positions of
each individual electrode are compared to a point of origin without taking into account
symmetries imposed by the use of a measurement method (SEV Wenner or SEV
Schlumberger).
With this view mode, it is possible to change the position of a single electrode
independently of the symmetry rules imposed by the used method, and this modification
will be displayed and stored on the session file.
In the view mode called "Simplified, if possible", a partial view of the contents of the
session file is shown to the operator, the "Simplified" view, in such a way that the
redundant information due to the symmetry imposed by the method is hidden to the
operator.
With this view mode, only the parameters displayed are allowed to be changed, and the
program will take care to maintain the symmetries imposed by the measurement method
used for the session.
The "Simplified" view, being constructed from the complete data of the table, will be
used by the system only in cases where the following two conditions are met.
- You are working on a session using a symmetric electrode position method (SEV
Wenner and SEV Schlumberger for complete measurements).
- For the geometric positions of the electrodes, the conditions for the simplification of the
values must be respected.
So, for the measurement sessions carried out with the SEV Wenner or SEV Schlumberger
method and that comply both conditions: distance between the electrode M and the origin
equal to the distance between the origin and the electrode N, the session will only display
the AB / 2 distances (half the distance between electrodes A and B) and MN / 2 (half the
distance between the electrodes M and N).
Meaning of the Sigma value for a complete measurement
The Sigma value associated with the measurements is calculated as the average square
deviation of the measured value of R and then reported as a percentage on the value of R
itself. It gives an indication of the variability of the repetitions of the measure with respect
to the average value, and therefore a measure of the goodness of these measures: the lower
the calculated Sigma, the more the measurements are close to the average R value and
therefore the measurement is precise.