On Friday 08 May 2020 12:09:45 Dan Henderson wrote: > Thanks Andy/Jon/Gene. To enable Quadrature do I merely turn on > phase-A/B/index inputs and remove “encoder-counter-mode = True”? > Sounds good.
> Here’s a pic of the reverse circuit I’m making to enable M4 polarity > reversal of the DC motor. We all know this stuff runs on smoke and mirrors. That controller probably will NOT like being reversed without first stopping the motor, then reverse that relay and restart the motor. Doing otherwise will probably break the mirror and let all the smoke out. Typically they don't work anymore. Ideally, two relays. I have used the P&B ice cubes with 20 amp contacts for this. One to apply a braking resistor to absorb the motors energy as its stopping and a second to do the reversal. Its wired closest to the motor with the moving contacts to the armature. A calrod coil out of an electric cookstove makes a good braking load. Somewhat overkill but 100% serviceable forever. The reversal sequence would be: 1. hold the reversal from motion, blocking it from the controller 2. use that to reduce the drive to zero useing a rate limiter like a limit3, switching its input with a mux2. 3. When the drive is off, switch on the load R relay to stop the motor much quicker. 4. when, according to the encoder, the motor has stopped, release the braking relay, 5. enable the reversal relay AND restore the speed input to the limit3 and let it ramp the motor back up to set speed Do the same thing in reverse at the top of the backout move. hint, an xor2 is used to detect the change in state of the rev signal from motion. A miss-match is the trigger for the stop sequence. I ran my 7x12 that way for about 2 years without letting the smoke out. But with a heavy 5" chuck, the overshoot at the bottom of the hole was terrible. So I eventually threw more money at it. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
