Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: Mr.Chips on April 23, 2020, 01:25:28 PM

Title: Add 2nd DRO for Y axis
Post by: Mr.Chips on April 23, 2020, 01:25:28 PM
How can I add a second DRO to monitor the Y Slave (C) axis I’m having problems with lost steps and would like to monitor both the Y master and Y slave movement.
Thanks
Title: Re: Add 2nd DRO for Y axis
Post by: joeaverage on April 23, 2020, 03:46:29 PM
Hi,
even if you add another DRO it would display the commanded position only. If a stepper loses steps Mach dosen't
know. So the commanded position could be '2000' say butthe stepper has lost five and is actually at position '1995' but
the DRO is still going to say 2000. What does a second DRO gain you?

Craig
Title: Re: Add 2nd DRO for Y axis
Post by: Mr.Chips on April 23, 2020, 06:04:05 PM
Got it, I was hoping that it recorded the actual position rather than the Command.
Thanks
Title: Re: Add 2nd DRO for Y axis
Post by: joeaverage on April 23, 2020, 06:15:14 PM
Hi,
if you had an encoder on the stepper then yes the second DRO would record the actual position so you
could see the difference between commaned and actual positions.

The expense and complication of doing that would be better invested in fixing the fault that causes lost steps.

I use Vexta steppers and Vexta drivers, they are great, not hugely powerful but because they have low inductance and the voltage
of the driver is a whopping 150VDC they really sing. I have not lost a step in five years.

Craig