In Reply to: Re: UL vs IEC Creepage requirements posted by colin howard on 01/09/02 at 10:47 PM:
Hi, Colin and Kevin.
The term "creepage" in this context comes, I think, from the colorful mental image of something nasty gradually creeping its way along that shortest path until finally it causes a breakdown to occur.
It's origin is from the realm of high voltage. High voltage breakdowns don't always happen all at once; they may take a while to manifest themselves.
You'll notice that high voltage isulators used on power transmission lines for example, have multiple disc structures. These are designed to increase the creepage distance between two points which separated by a very high voltage in order to minimize the creepage effect.
John Dunn - President
Ambertec, Inc.
ambertec@ieee.org