Author Topic: Gross loss of position using servos and encoders with Galil  (Read 286 times)

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Offline bbutcher

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Gross loss of position using servos and encoders with Galil
« on: September 09, 2018, 01:57:07 AM »
I have a weird problem. I am running a DMC 1750 Galil controller with servo motors and US Digital encoders. I have two Mach 3 profiles that I can use, and in one profile the DROs update while manually turning the motors. In the second profile, the DROs do not update while manually turning the motors. The DROs work correctly in both profiles when the motors are being driven.  With motors off, I can move one or two inches and restart the motors with the DRO now updating from the old position (a loss of position of 1-2 inches, i.e. 20000 to 40000 encoder counts in my system).


This is with the two profiles operating on the same hardware with no changes other than opening a different profile. Both profiles are configured to disable the motor amplifiers on E-stop.

I still seem to be communicating with the Galil controller since I can activate a limit switch and see the change on the diagnostic page, both with and without motors activated.
« Last Edit: September 09, 2018, 02:00:09 AM by bbutcher »

Offline bbutcher

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Re: Gross loss of position using servos and encoders with Galil
« Reply #1 on: September 09, 2018, 12:37:12 PM »
I just verified that the DP counter in Galil is being incremented as the motors are being turned manually. I also verified that the DROs are not being incremented or updated when high voltage is turned off to the motors whether Mach3 is reset or not. Note that the old profile only has 3 axes and the new profile has 4 axes, although I have not activated the motor for the 4th axis in Mach3 Motor Output since the actual motor and encoder is not connected at this time.
« Last Edit: September 09, 2018, 12:46:14 PM by bbutcher »

Offline bbutcher

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Re: Gross loss of position using servos and encoders with Galil
« Reply #2 on: September 10, 2018, 12:37:24 AM »
I also uninstalled Mach3, deleted everything with Mach3 from the registry, and re-installed it. Same result.

Offline bbutcher

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Re: Gross loss of position using servos and encoders with Galil
« Reply #3 on: September 10, 2018, 09:58:05 AM »
Please note that these servo motors are not being driven by step and dir signals. The motor amps use a +/- 10V signal for motor drive.

Offline bbutcher

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Re: Gross loss of position using servos and encoders with Galil
« Reply #4 on: September 10, 2018, 02:14:49 PM »
I found a solution that seems to work. I am using the ver 4.4 of GalilMP3 and everything seems to work fine now. I am able to repeatedly config the plugin which would not work in ver 4.6, and the DROs now read when manually turning the motor. In ver 4.6 the DROs seemed to be getting their position value from the motor move signal in Mach3 much the same as it would with stepper motors. Manually moving the motors would not ever update the DROs, even with Mach3 reset and the High voltage turned off to the motors to allow moving them when they should be locked.
Smurf says ver 4.4 is long gone, which must mean someone destroyed it or maybe Newfangled Solutions just wants to sell Mach4?