Re: [CAD_CAM_EDM_DRO] re: boom

At 12:33 PM 8/6/02 +1200, you wrote:

>In either case the driving circuitry should be protected from the emf (to a
>certain extent) by the proper use of a snubbing circuit.

Precisely my point. Chopper driver disconnects windings MANY orders of
magnitude more often than unplugging, so any damaging effect if it exists,
is going to occur many orders of magnitude more often in normal operation
than in any now and then disconnects. So, if this is normal in ordinary
service, it behooves driver mfgr to be ready for it.

>Disconnecting the
>windings whilst current is flowing through them (in either the hold state,
>or whilst moving) is not a good idea, although I'm sure we're already
>decided on this.

It may or may not be a good idea, but it's probably no badder than just
running them. The effect on the connector itself is the most valid objection.