Positron 3782651U/50, Руководство пользователя

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Interpreting Graphic Results
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Graph of faulty insulator
adjusted to 60% opaqueness
superimposed over established
E-field Signature Reference for
comparative analysis
Reference E-field
Signature graph of
“healthy” insulator
derived from testing a
number of known good
insulators
C) Contains detailed information of the scan.
a.
“2017/03/30” indicates the date of the scan
b.
“UTESTER” indicates that the a Universal Tester was used
c.
“t = 56770”
indicates the number of seconds since midnight,
d. “Line: 0033 Tower: 1028 Phase U String: 01” identifies the tested insulator,
e. “User code: R1” can be any code defined by the user,
D) “Point number” indicates the tested point number along the insulator.
6.2 Linear / Log Graphic Options
The “Linear” display mode is used to display the electric field readings from the Probe on a
linear scale. It is used for lower voltage applications (13 or less points).
The “Log” display mode is used to amplify the small variations in the lower portion of the curve.
It is normally used for higher voltage applications (14 or more points).
The Windows-based Insulator Tester software allows you to toggle the scale of the graphs being
viewed between
Linear and Logarithmic scale for 14 or more points. Only Linear scale is used
for 13 points or less.
6.3 Interpreting Results
On lower voltages insulators, such as 25kV used for electric railways, a comparative
methodology for determining the relative health of an insulator is required.
It is recommende
d to test several identical insulators to obtain a graphic “health signature”
for those particular lower voltage insulators. This signature serves as the baseline for
evaluating like-insulators. As an example, on a 3-phase distribution line, the signature from
each phase should be identical. A minimum of 5 skirts per insulator is recommended.
The resulting graphs of the E-field of the insulators can be superimposed for comparison. By
placing one graph over the other and reducing the opaqueness down from 100, one graph will
become visible through the other. This method can also be used to evaluate the degradation
over time of a given insulator, using the Search button on the main screen.
Comparing Insulator E-field
Signatures Using Superimposed Graphs
Note: Establishment of a reference signature of “healthy insulators” may differ depending on local conditions.
As
such, the reference signature indicated in this figure is illustrative only.