limit switch settings impact y-axis movement ?

[domu]

I have china 17x15 gantry router from ebay conrolled from Mach3.

I decided to add limit switches using 3-wire PNP proximity sensors.
Electronic side works OK, but when limits are enabled in Mach3
Config -> Ports and Pins -> Input Signals -- movement on Y-axis
become jerky at random, like momentary binding / loosing steps.

That happen also when limit sensors are physically disconnected
from the controller board, so I guess it has nothing to do with
added circuits.

As soon as limits are disabled in software - problem is gone --
Y-axis movement is fine.

Now, that happen only when executing g-code - either from
program or MDI. It does not happen when jogging.

I am not even sure if this is controller board or Mach3 problem.

Did anyone experienced anything similar ?

Thank you in advance for any helpful answers.

[robe_uk]

It does sound strange, the fact the even with the circuits disconnected and limits enabled would suggest to me that it may well be a setup issue, double check(am sure you have but lets humour me) the pin and port number you have set for all your limit input and motor signals to make sure you haven't used the same pin number twice.
Am not expert so outside of that I have no other advice.

Maybe post a quick sketch of how you wired it all up incase there is something wrong and you are pulling the port down, although this is unlikely.

Rob

edit: reread your post and you say it doesnt happen when jogging, mmm maybe post a screen shots of your config screens and someone might be able to spot something.

[domu]

Hi Rob,

that sounds like a good idea, thank you.

Please see attached files.

Some coments to attached pictures.

1 Y-axis works OK.jpg and 2 Y-axis binding problem.jpg
- just as in the name - the only difference in settings which makes
Yaxis work find or randomly chatter and bind.

3 Motor tuning Y-axis.jpg
- Y-axis - is the same as X-axis - worked fine until now.

4 General config.jpg
- just in case if there is something that could contribute to the
problem

5 Motor Home-Soft_Limits.jpg
- I have try various settings but apparently did not make any
difference, so is back to defaults.

6 sensor interface schematic.jpg
- it is likely irrelevant, but as you can see I was, may I say,
over-protective ? Since I have no experience with inductive
proximity switches - I have separated sensors from controller
logic by relays.

7 controller port closeup.jpg
- here you can see connector on the controller where sensor
interface board is connected (blue arrow).

I must say, I am totally at loss with this one.

Any ideas appreciated.

[robe_uk]

maybe you could try some debounce in the general config screen, I hope someone can chime in and help.

Good luck
Rob

[domu]

One more thought. I just realize that Y-axis was giving me problems
from the very beginning. While X and Z was always working nice and
smooth, Y was louder, sound choppy, tend to bind or loose steps
occasionally. By switching X and Y I have narrowed problem to the
controller.

Since I am using another variety of Chinese TB6560 controller, and
I heave seen number of posts here about problems with them - would
it be possible that logic circuitry behind optos (?) someway interfere
with TB6560 controlling Y-axis section ?