Re: blown Gecko - shorted output ?

Hi Dave,
I hope it's not one of those situation where,
the "drive blowed up real good" but didnt show it, then took out
the previous motor tried afterward. If you can, ohm out all the
motors again coils and to the motor case.

Those look like the early G201's, I wonder if the anodizing used
as insulation on the Gecko backplate on the mosfets may have
scratched thru by vibration and failed. Its sorta hard to tell
after the fact, but Mariss may interested in a postmortem.

At this point, I'd try out the motors with a surviving G201 as
another reality check. On the bench isolated .

(Sounds like you have this already covered)
And put a *big* 10ohm resister or a smaller car headlight in series
with the power supply and the drives till you get it ironed out.
This should help protect the drives and still deliver usable current
at low loading. Also try remounting the motors, but leave the
belts/couplers off for no loading.

-Lee



--- In CAD_CAM_EDM_DRO@yahoogroups.com, "turbulatordude
<davemucha@j...>" <davemucha@j...> wrote:

> Hi Lee,
>
> One thing that bothers me is that it ran on a NEM23 for months

before

> I switched to the Nema34's.
>
> now nothing seems to work. I figured it was a bad motor so switched
> back to the NEMA23 and pop. as you might imagine testing with new
> drives is not fun or cheap.
>