PASI GEA RM1 1.0, Руководство пользователя

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10
Measurements are started from low AB values (see Table ExampleSCH Figure 7 and
Figure 8) and we proceed by enlarging the measure, for some AB / 2 values (when the
Sigma value is too high) to avoid certain problems from lateral variations of surface
resistance it is appropriate to re-execute the measurement by increasing the value of MN
/ 2 (re-tie, see Figure 9 and Figure 10 Figure 9), ideally the two measurements should be
the same.
As you can see from the attached table the values of AB / 2 are spaced logarithmically
with 10 values per decade (1-10 m; 10-100m; 100-1000 m; etc.) and initially all MN
values are equal, (Figure 4 ).
When the measurements begin to be noisy (standard deviation> 5% the contact resistance
must be decreased with the methods indicated above to allow greater current flow and
simultaneously increase the MN / 2 distance, as the measurement proceeds if the Sigma
is to exceed at the prefixed value it will be possible to press the execute / modify / repeat
key (Figure 11) and the software (if the measurement had already been performed it will
increase all the values of MN following one of a value equal to ¼, will be simultaneously
updated the values of K from the modification point, we will proceed as above until the
Sigma will again be> 5% and then again it will be necessary to increase MN, pressing the
repeat key measures all the data from the point of modification forward will be increase
by ¼ and proceed until the end of the measures.
F
IGURE
6 - SAVING THE TABLE