Need Help! Getting False Limit Switch Triggers.

27 May.,2024

 

Need Help! Getting False Limit Switch Triggers.


I am in the final process of finishing my first DIY CNC machine. I can jog all my axis but I constantly get interrupted by false triggers from my limit switches.
I have currently re-wired everything with the exceptions of my power supplies with shielded wire and I am still getting false triggers. Although my E-stop appears to not be triggering anymore.

From what I read this is not a way to solve the problem but a workaround. I got some 0.1uF capacitors to try and stop the noise and I could not get a signal into Mach 3 with them in the circuit. Diagnostics page had all the switches lit up. I used

Tried debouncing in mach3 with no luck. Almost seemed to have no effect at all even at .

The whole wiring process is completely new to me and I think I must have ground some shielded cables to the wrong place or maybe the power supplies are too close to the BOB?

My next course of action I am thinking is getting ferrite beads for power supple cables. Or trying a whole new BOB system.

Sorry this is another post on an already common issue but I have tried doing the research in forums and trying to find any DIY build video with this breakout board and I still can not figure this out.
This has been very new to me, a project way harder then expected. Any help would be very appreciated!

I will attach images of my electrical plans I made and attach pictures of my wiring and cnc machine.

Hello,I am in the final process of finishing my first DIY CNC machine. I can jog all my axis but I constantly get interrupted by false triggers from my limit switches.I have currently re-wired everything with the exceptions of my power supplies with shielded wire and I am still getting false triggers. Although my E-stop appears to not be triggering anymore.From what I read this is not a way to solve the problem but a workaround. I got some 0.1uF capacitors to try and stop the noise and I could not get a signal into Mach 3 with them in the circuit. Diagnostics page had all the switches lit up. I used https://www.amazon.ca/gp/product/B00...OUHD0RRM&psc=1 and tried putting them into all the limit switch inputs (Input 10, 11,12,13) on the BOB. They have been removed.Tried debouncing in mach3 with no luck. Almost seemed to have no effect at all even at .The whole wiring process is completely new to me and I think I must have ground some shielded cables to the wrong place or maybe the power supplies are too close to the BOB?My next course of action I am thinking is getting ferrite beads for power supple cables. Or trying a whole new BOB system.Sorry this is another post on an already common issue but I have tried doing the research in forums and trying to find any DIY build video with this breakout board and I still can not figure this out.This has been very new to me, a project way harder then expected. Any help would be very appreciated!I will attach images of my electrical plans I made and attach pictures of my wiring and cnc machine.

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Limit switch being triggered whilst homing?



So I have messed with the acceleration settings of the motors and it made a very slight difference I think but it did not solve the problem of going to far after hitting the home switch.

I have also tried adding debounce (up to from 0) in the general config settings however that dident seem to make any difference to the problem I have when limit switches are enabled.

I have however found a way of homing without my machine trying to destroy itself, that was to turn the homing speed down to 3%, that way it doesn't go far past the switch before it backs off. (This is still with the limit switches turned off)

Im not sure if it makes a difference but the Diver board im using is DDSM4V5.0, which came with a DDream plugin for Mach 3. In the manual it recommends going to the plugin config and adding the following values which is what I currently have set. Should I be changing these settings to something else in the plugin config?

Device Buffer: 400ms

Jog Buffer: 100ms

-----------------

I do however have a new problem though which I dident notice before., My machine wont home Y axis, it does Z, the X and thinks that it is finished. I have checked Y axis is enabled everywhere I can think of and I am able to jog the machine along the Y axis with no problems. Also upon importing Gcode it doesn't show up in the table view so I think the machine must think it cant use Y for some reason? Any ideas? -

Thanks guys,

Thanks guys,So I have messed with the acceleration settings of the motors and it made a very slight difference I think but it did not solve the problem of going to far after hitting the home switch.I have also tried adding debounce (up to from 0) in the general config settings however that dident seem to make any difference to the problem I have when limit switches are enabled.I have however found a way of homing without my machine trying to destroy itself, that was to turn the homing speed down to 3%, that way it doesn't go far past the switch before it backs off. (This is still with the limit switches turned off)Im not sure if it makes a difference but the Diver board im using is DDSM4V5.0, which came with a DDream plugin for Mach 3. In the manual it recommends going to the plugin config and adding the following values which is what I currently have set. Should I be changing these settings to something else in the plugin config?Device Buffer: 400msJog Buffer: 100ms-----------------I do however have a new problem though which I dident notice before., My machine wont home Y axis, it does Z, the X and thinks that it is finished. I have checked Y axis is enabled everywhere I can think of and I am able to jog the machine along the Y axis with no problems. Also upon importing Gcode it doesn't show up in the table view so I think the machine must think it cant use Y for some reason? Any ideas?Thanks guys,

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