[Old_Phart]

I am using Clearpath motors on my DIY router. Mach 4 on a win10 current model PC and a PMDX-126 BOB and ESS. I have been fighting the HOME limit switches. It seems that the motor coasts past the point where the limit switch makes contact. This makes it crash into the bumper and fault the Clearpath motor.


I wish I could make the CP motor stop faulting but it seems that is not an option.


I know the CP motors don't actually coast and this happens on every axis so I expect the motor is ramping down to zero. So where would there be a setpoint to shorten the delay between the limit switch activation and the motor stopping?


What is a reasonable distance (or time) between the limit switch activation and the motor stopping moving? I only have about a 1/8 of an inch travel between them.


I know people use prox sensors and their range is not huge so certainly I have something set wrong or more people would be discussing this issue.

[Jim Dawson]

Seems like 1/8'' might be a bit close. I guess you could increase the acceleration, but that might cause other problems. The best way would be to move the LS actuation point, maybe 1/2'' or greater.

[Old_Phart]

Increase Acceleration also increases Deceleration? I had not considered that. I assume you could control each independently.

A typical prox switch doesn't typically have much more range than 1/8 that does it?

And to clarify I am talking about the HOME position switches that zero the DRO. There are limit switches for the end of travel but I am not talking about those.

[Jim Dawson]

OK, that is a bit different. Slow down the homing routine seek speed. I would still move the switches, a home switch can be anywhere. The actual home position can be an offset from the switch.

[Old_Phart]

Yea I'll move the switches. I changed the acceleration and that does the trick,but I'm playing with fire by not allowing some overtravel. I guess I can only hope the overtravel is consistent

[GME]

Try going into your ESS plugin and look at the homing settings. IMO, you want your homing sequence to be really slow, like 5 ipm. It's settable in the ESS config. Just know that you will need to move axes close to the sensors before starting the Reference All routine, or you will be waiting forever for the machine to home.

Gary

[Old_Phart]

I slowed down the travel and changed the switches, it's working well now. That was my problem, I expected it be fast and work and it just isn't like that. Physics kicking my butt again.
I would like to implement a 2 stage home sequence like on the touch probe. Rapid till the switch triggers, then back off and slow to it for repeatability.
But I'll dig into that later.