Marvin Kaye <marv@lancaironline.net> wrote:
>
>
> ... so he purchased one of Bob Nuckoll's crowbar
> modules and had it sitting unused.  When installing the ground power system I
> decided to incorporate the crowbar circuit to protect us against the
> possibility of a line guy accidentally hooking up a 24V GPU and blowing things
> up.  

   Indeed, the contactor method does have the additional
advantage of using lower current components for the crowbar
circuitry, since it only has to short out the low-draw contactor coil.  I like that.  I'd like it even better if
the contactor was a stepping relay and the crowbar actuated
the stepper to the "off" position.

Regards,
Dale R.


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