Bill,
You might want to look up some old papers by Masamitsu Honda (do a search for “M Honda ESD IEEE”). He did several studies on the variables that affect the severity of the discharge with regards to equipment malfunction. My guess is that on your longer arcs more energy is going into light and sound than into the EM fields, whereas with your shorter arcs you get more fields but less zap. Also faster rise times, so more energy at higher frequencies. Just a SWAG. Regards, Rob From: Bill Owsley [mailto:[email protected]] Sent: Tuesday, May 19, 2009 2:48 AM To: [email protected] Subject: Re: [PSES] ESD testing <snip> Now if I get the time (doubtful) I'll see what the variables are in voltage and spacing of the vertical groud plane to horizontal ground plance. ps. It has been observed that the longer sparks - more distance, does not cause the same problems. But contact discharge to date has not either. </snip> - Bill Indecision may or may not be the problem.
