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discharege normally. The impulse flashover fault point whether
discharge normally can be detected by the whole wave form.
E.It can detect whether there is a fault of spark-over flashover
phenomenon by the sound of the gap sphere dischargin and
indicator of the electric meter. If the discharging phenomenon
does not clear, it can add the voltage, sphere gap, or the capacity
of storage capacitor.
F. The testing of the fault distance is as the same as before.
4) Waveform comparison method
A. Disconnect all equipment from the cable under test;
B. Connect the normal cable to the output port of the tester.
C. Use the low-voltage pulse method to read the measurement
waveform of the normal cable and save it.
D. Connect the faulty cable to the output port of the tester and
measure its reflected wave;
E. Find the saved waveform;
F. Compare the differences between the two waveforms and find
the point of failure.
IX. Announcement
1. In the method of impulse testing, it shuold drop off any inside
devices and do the testing on the outmost line.
2. In the method of flashover testing, it must turn the switch to the
position of flashover.
