In message <[email protected]>,
dated Tue, 13 May 2014, "ce-test, qualified testing bv - Gert Gremmen"
<[email protected]> writes:
Electrochemical reactions behave like charging a battery, it is the rms
value that determines the charge, not the peak value.
I don not agree. I looked for a simple explanation on the web, but so
far I found only quite complicated explanations based on the Nernst
equation. However, I think you may see that the transfer of electrons
from one substance to another, driven by an externally-applied electric
field and creating conductive species, includes neither a squaring
process or an averaging process. It's simply the reaction of the charged
electrons to the field, and the field strength depends on the
instantaneous voltage, not the RMS.
However, I did explain that using the peak voltage is a *prudent*
assumption. If it proves costly, a lower creepage distance should be
tested, but it's difficult and costly to test anything that depends on
pollution. Again, you can be *prudent* and test with a worst-case
pollutant, soot or carbon from motor brushes.
--
OOO - Own Opinions Only. With best wishes. See www.jmwa.demon.co.uk
Nondum ex silvis sumus
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK
-
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