Hi John,
The timing of microseconds is orders of magnitude slower than the size
of the test setup relative to the speed of light in conductors, 1 ft/ns
in free space and maybe 1.5 to 2 ns/ft in most conductors. The test
setup used about six feet of cable, 12 ns at most.
The applied voltage of the pulse was much lower than rated breakdown of
power supply, less than 500 Volts.
I have added the results to my planned (every) Thursday presentation via
web which this weeks describes ESD as a stress that causes this also.
Doug
University of Oxford Tutor
Department for Continuing Education
Oxford, Oxfordshire, United Kingdom
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On 11/4/14 11:54 AM, John Woodgate wrote:
In message <545898ce.1050...@emcesd.com>, dated Tue, 4 Nov 2014, Doug
Smith <d...@emcesd.com> writes:
Tonight, I was able to create the same effect using EFT (electrical
fast transient) pulses. Some power supplies can take a single EFT
pulse and a microsecond to several microseconds later generate one or
more EFT pulses, some larger that the stimulus one, embedded in
corona discharges!
Is this some sort of St Elmo's Fire effect, i.e. RF energy scoots
around 'trying to find' a pointed conductor to discharge from? I
suppose 'several microseconds' can be understood in terms of the
propagation of the energy being much slower in conductors than the
speed of light.
-
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