On 10/18/2020 6:38 PM, Phil Allison wrote:
David Farber wrote:

====================


By the way, I noticed a potential problem with checking the input
waveforms to the gates of Q800 and Q802. If I put one scope probe across
one transisor, from G to E, that should be OK however if I want to see
both waveforms together while powering up the unit and then connect a
second probe to the scope on the other transistor, the common ground of
the probe will short out Q802. Should I just float the ground on one of
the probes? Will that work?



** Both signals come from the same transformer - out of phase.

You can monitor the outputs of the 3525 IC or the primary side of the tranny without the iso in use.

Plus check continuity of secondary windings and their connections to the IGBTS.

.... Phil


Thanks for following up with the details Phil.

--
David Farber
Los Osos, CA