HTC CE-8201, Manual, Page: 15 / 19

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computer side will not be connected. If you need to use the software on the computer
side, please disconnect the Bluetooth connection on the mobile phone before using it.
3) After successful connection, it can operate test and display online, browse history storage
data, and set alarm value.
XII. Field Application
1
!
Multi-point grounding system
For multi-point grounding systems (such as power transmission system tower grounding,
communication cable grounding systems, certain buildings, etc.), they are connected by
overhead ground wires (the shielding layer of communication cables) to form a grounding
system. See below. When measuring with a clamp meter, its equivalent circuit is as follows:
R1 is the predicted grounding resistance.
R0 is the equivalent resistance of the grounding resistance of all other towers in parallel.
Although, from the strict grounding theory, due to the existence of the so-called "mutual
resistance", R0 is not a parallel value in the usual electronic technical sense (it will be slightly
larger than the parallel value in the electronic technical sense), but, Since the grounding
hemisphere of each tower is much smaller than the distance between the towers, and after all,
the number of grounding points is large, R0 is much smaller than R1. Therefore, it is reasonable
to assume R0=0 from an engineering perspective. In this way, the resistance we measured
should be R1.
Several comparative experiments with traditional methods under different environments and
different occasions prove that the above assumptions are completely reasonable.
2
!
Limited point grounding system
This situation is also more common. For example, some poles and towers are connected to
each other by overhead ground wires; for example, the grounding of some buildings is not an
independent grounding network, but several grounding bodies are connected to each other
through wires.
In this case, if R0 in the above figure is regarded as 0, it will bring a large error to the
measurement result.
For the same reason as above, we ignore the influence of mutual resistance, and calculate
the equivalent resistance after the parallel connection of the grounding resistance in the usual
sense. In this way, for a grounding system with N (N is small, but greater than 2) grounding
bodies, N equations can be listed:
T
N
R
R R R
R
2
3 1
2 1
......
1 1
1
=
+ + +
+