RigExpert AA-2000 ZOOM, Руководство пользователя

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User’s manual
Theory
Time domain reflectometers ( TDR ) are electronic instruments used for locating faults
in transmission lines.
A short electrical pulse is sent over
the line, and then a reflected pulse is
observed. By knowing the delay between
two pulses, the speed of light and the
cable velocity factor, the
DTF (distance-
to-fault) is calculated. The amplitude
and the shape of the reflected pulse give
the operator idea about the nature of the
fault.
Instead of a short pulse, a “ step” function
may be sent over the cable.
32
Annex 5
TDR mode