Hello,
I frequently get error messages from pathpilot when I am referencing the axes on my 440. The error states that limit switch contact duration was too brief during axis reference operation. Try repositioning limit switch to improve dog engagement or consider replacing switch. This has happened on both the x and y axes. This is kind of an intermittent issue; is there any way to make this robust? I guess I don’t really understand what is going on; why contact duration would be brief, or why they would need repositioning when they are locked down. Just wondering if anyone else has had this and what they did to “permanently” solve it. Thank you
I had this same error on my machine last year on the Y. I checked wiring and that looked good, so I ordered a switch.
While I was waiting for a new switch to arrive I opened the switch and it had quite a bit of coolant in it, some corrosion and some fine metal powder. I cleaned it out, sanded the contacts with 800 grit paper and greased it with dielectric silicone grease.
I still have the new switch waiting on the shelf for when the time comes, but the original has been back in action for 7 months now without a hiccup.
Edit 1 & 2: I can’t remember if my machine threw the same error, but I pulled both X and Y switches. X was a bit dirty and dry, so I cleaned it and threw in a little dielectric grease. Y was definitely the problem on my machine.
Agreed on thorough cleaning or replacement.
We have another discussion on the limitations of these switches/repeatability. Do you have accumulated chips on/around the bumpers or the switch?
Think of how it homes in terms of how that relates to your error.
The machine approaches the limit switch at a faster speed from whatever initial position it is at when called upon to reference to initially find the limit switch, then it approaches it again at a slower speed, as I would understand, the second run is for accuracy/repeatability and what it would actually use. The controller is able to time how long from where it was commanded to move from where it was moved to after the initial contact to the second contact.