Megger PFL22M1500 Series, Руководство пользователя

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AVTMPFL22M Rev 1 April 2011
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Description of Arc Reflection
The Arc Reflection method uses standard pulse echo techniques to prelocate
high resistance faults, which are not identifiable using pulse echo.
In Arc Reflection we use an Impulse Generator, Arc Reflection Filter and the
MTDR100. The operator takes a standard pulse echo trace which is
automatically saved as a reference file. Then a HV impulse is applied to the
cable, the impulse going through the Arc reflection filter. This arc reflection
filter “stretches” in time, the outgoing pulse which then ignites the fault, creating
a temporary bridge to earth/ground. During this period the MTDR sends out
LV TDR pulses into what is in effect a short circuit. This trace is then
memorised and compared to the original trace. The point of divergence is the
point of fault.
Typical Traces
This method is extremely effective and easy to interpretation.