Positron 3782101C/50, Руководство пользователя

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Overview
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2.2.1 Recommended Testing Methodology:
Testing insulators when dry using the Positron testers will only detect conductive defects in the
insulators. Testing the insulators when moist, the Positron testers will detect defects in the
insulators as well as conductive defects due to pollution.
When a flashover occurs in a region, it is prudent to test not only the flashed over insulator, but
also other insulators in that area. The likelihood is that if one insulator flashed over, other
adjacent or nearby insulators will be similarly covered by a pollutant film and should be tested
as they are also likely to flash over in the near future when moistened by rain or early morning
dew.
If the railway operator gets readings on many insulators in a region that show high conductive
pollution on insulators, the railway operator will know which groups of insulators should be
changed or cleaned at one time as a preventative maintenance measure. This minimizes
interruptions or downtime of rail traffic as well as minimizing danger to any maintenance crew
whether working underneath the high-voltage lines per their routine schedule. The Tester will
act as a Health detector of the insulators tested in advance of any failure.
Whether or not the insulators are cleaned, the Positron Tester will detect conductive defects
whether due to an internal defect in the insulator or due to surface pollution conductive defects
under moist conditions. It is possible to test segments of the electrified insulators along a line to
determine if they are defective, or if they will flashover due to pollution accumulation.
2.2.2 Advantages of Using Positron Testers (PID)

Health detection of overhead insulators in advance of any failures;

Enables the use of a defined maintenance schedule;

Safety of maintenance crews and other personnel doing proximity works;

Detects all internal insulator conductive defects;

Detects defects due to surface contamination (moist conditions may be required to
detect certain defects);

Prevents outages and railway traffic delays;

Reduces time to find defects and to perform appropriate maintenance;

Reduces costs (for maintenance and operation of the railway traffic).