Barry, I could be wrong, and if so I would stand corrected, but from my basic electronics training, I recall that electron flow is from negative to positive.
I also recall being taught that lightning actually travels from earth (neg. charge) upward to the positive charge of the clouds. Then there is also the case of lightning between clouds of opposite charge, and again the electron flow direction is from neg. to pos. Ross -----Original Message----- From: Barry Ma [mailto:[email protected]] Sent: Wednesday, October 04, 2000 5:58 PM To: [email protected] Subject: Re: ESD Opportunities Please allow me to ask a relevant question only for curiosity. We have no idea of what charge (positive or negative) would go to the DUT in ordinary ESD. That's why we have to test two polarities in ESD immunity test. Lightning is a kind of ESD happened between a charged cloud and objects on earth surface. Some figures imply that an electron current flows from the charged cloud to the earth. Is it possible to have an opposite direction - electron flows from earth to cloud? Thanks. Barry Ma _______________________________________________________________________ Free Unlimited Internet Access! Try it now! http://www.zdnet.com/downloads/altavista/index.html _______________________________________________________________________ ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected] ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected]
