ADInstruments AD6412 Manual De Usuario página 43

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R 
N
1
R
1
Where: R1, R2, ......R
R ,R ,......R
1T 2T
grounding branches.
It is nonlinear equations with N unknown numbers and N equations. It indeed has a
definite solution, but it is very difficult to solve the issue artificially, even impossible when N
is larger.
Therefore, you're expected to buy the Limited-Point Grounding System Solution software
produced by this Company. Users can use the office computer or notebook computer to
carry out solutions.
In principle, in addition to ignoring the mutual resistance, this method does not have the
measurement error caused by neglecting R
However, users need to pay attention to that: in response to the number of the grounding
bodies mutually linked in your grounding system, it is necessary to measure the same
number of the testing values for calculating of the program, not more or less. And the
program would output the same number of grounding resistance values.
3. Single-Point Grounding System
From the measuring principle, AD6412 series Meter can only measure the loop resistance,
and the single-point grounding is not measured. However, users will be able to use a
testing line very near to the earth electrode of the grounding system to artificially create a
loop for testing. The following presented is two kinds of methods for the single-point
grounding measurement by use of the Meter. These two methods can be applied to the
occasions beyond the reach of the traditional voltage-current testing methods.
Two-Point Method
As shown in the figure below, in the vicinity of the measured grounding body R
independent grounding body of better grounding state R
or a building). R and R
A
As the resistance value measured by the Meter is the value of the series resistance from
the testing line and two grounding resistances.
Where: R is the resistance value measured with the Meter.
T
R is the resistance value of the testing line. Meter can measure out the
L
resistance value by connecting the test lines with both ends.
©Copyright Abacanto Digital SA.
1
R
NT
1 1
......
  
R R
2 ( N  ) 1
are grounding resistances of N grounding bodies.
N
are the resistances measured with the Meter in the different
NT
line will connect to each other using a single testing line.
B
R =R
T A
Manual de usuario AD6412
.
.
0
(for example, near a water pipe
B
+ R + R
L
B
AD Instruments
find an
A,
43