Re: gecko burned again

Jon, it makes sense that something external to the drive is the
problem, but the motors are new and not wet. I don't understand how
a new motor would have internal shorts. Does it make sense to
replace all the wiring between the motor and the other components to
eliminate the possibility of a short externally?

Thanks

Keith

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@p...> wrote:
> Keith Clark wrote:
>
> >Well, the y axis gecko drive burned again this morning. This
time
> >there are no loose wires. I was doing very little with the
machine
> >and had just turned it on when during a y axis G0 move, the drive
> >burned up. I assume this is an indication that the Gecko cannot
> >handle the motor I am using. This is an old topic and I have
asked
> >for help with this problem before. The mill is a Bridgeport
Series
> >1 CNC originally controlled by Boss 6 but now using Anaheim Nema
42
> >high torque stepper motors and Mach2 software with a Campbell
> >breakout board.
> >
> >At this point is seems reasonable to try another brand drive?
> >
> >
> I think you need to retire that MOTOR. There is nothing wrong with
> the Gecko drive, when used with good motors. But, one of its
weaknesses
> is that shorts to ground, or just plain internal shorts in the
motor
> windings
> will pop transistors in the Gecko drive. I think you'll find the
Rutex,
> Xylotex,
> etc. drives all have this same weakness. After blowing TWO Geckos
on
> the SAME motor, doesn't that tell you something? Why didn't the X
or Z
> drivers blow? Why always the Y axis?
>
> Explanation: Your Y motor has an intermittent short. How much
you are
> doing with it doesn't make much difference. I assume the motors
heat
> up, even when idling. The heat probably causes the short to
develop
> every once in a while, when the winding expands from the heat.
>
> Jon