On Sun, Feb 10, 2013 at 6:59 PM, Gene Heskett <ghesk...@wdtv.com> wrote: > > 1 microsecond can be an eternity to an IGBT. As for your spikes, make sure > that the scope is /not/ grounded thru its power cordage, but is grounded > locally to your circuit. Even a 6" ground lead can and often will show > over voltage spikes where there really aren't any.
I was just about to say that, but Gene beat me to it. Had an interesting discussion on the Tektronix listserv last week about exactly the same thing. The shorter the ground lead, the better. If you have a ground next to your test points, a short wire wrapped around the grounding section on your probe to the ground works the best - ie, your grounding lead ends up being about 1" or less in length. Tek used to make a grounding lead the snapped onto the end of the probe, and the lead on that was about an inch in length, or maybe less. Mark ------------------------------------------------------------------------------ Free Next-Gen Firewall Hardware Offer Buy your Sophos next-gen firewall before the end March 2013 and get the hardware for free! Learn more. http://p.sf.net/sfu/sophos-d2d-feb _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
