Compliance West MegaPulse 1.2x50-12.3PF-1, Instruction Manual

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Figure A 4. Arc - extinguish - re-arcing cycle.
Because of the circuit topology, these arc-extinguish transients will take place only at the tail of the
waveform, when the voltage is less than 50% of the peak output. Because the output is "clean" from the
peak to the 50% voltage level, the duration of the waveform is easily measured and calculated; the
transients have no effect on the calculation. In fact, the waveform definitions (from IEC 60060-1 and other
standards) do not specify the wave shape after the voltage has decayed to below 50% of the peak value.
In practice, these transients have no effect out the test being conducted however
these transients should not
be confused for a dieletric breakdown of the EUT . A dielectric breakdown occurs near the peak of the
impulse waveform as the voltage is still rising, or immediately after the peak. Figures A 5-7 show typical
waveforms when a breakdown occurs. These can be used as a guide for interpreting "failing" test results.