Re: [CAD_CAM_EDM_DRO] gecko burned again

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