Messages

1

General Mach Discussion / Re: Spindle Index anomaly [Hall effect - last stored RPM]

« on: February 28, 2018, 05:44:35 AM »

Cheers, I'll give that a spin.
However, it would be good to get to the bottom of why the DRO just retains the last seen value.

2

General Mach Discussion / Spindle Index anomaly [Hall effect - last stored RPM]

« on: February 28, 2018, 05:15:39 AM »

Hi Folks,

Just joined. I've got a Taig Mill which I'm running using Mach3 through a Gecko G540.
I recently updated the motor in the mill to a Brushless servo motor. As part of the upgrade, I can now use Mach3 to control the spindle speed.
Here's where I've encountered something weird.
I added a magnet to the spindle and used a Unipolar [non-latching] hall effect switch to measure RPM at the spindle. All works well, however, when I stop the spindle the RPM value in Mach3 retains the last seen RPMs. Does anyone have any ideas on what could be going on here? I've checked with a DMM and the HE switch activates in the presence of a magnet, and goes back to VCC when the flux field is far enough away.
It's not a massive issue, but it is bugging me, it is also causing problems calibrating the spindle, as that starts from 0, which is never 0.
Cheers