Hello Guest it is September 19, 2020, 06:08:25 PM

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Topics - jimstapenell

Pages: 1
1
G'day guys,

If this post is in the wrong place, can someone please advise where I should present this problem...

I have a 3040cnc router and have recently added limit switches (all in series). The system was working fine until a couple of days ago, my Z axis started to play up - eratic movement and occasional wrong direction. Found the problem - broken wire between controller and Z stepper motor.
So, I then replaced the 4 wire conductor between the control box and the Z stepper with shielded cable and grounded the screen/shield mesh wire at the plug where it attaches to the control box. The other end of the screen/shield mesh is not connected to anything.

I now have a problem that when Mach3, the router and the PC are running - and the router spindle is running, the X and Y axis motors creep - turn slowly and the red led's on the drive control boards (controller cover removed) for the X and Y axis light up intermittently.
If I switch off the spindle motor the X and Y axis are steady and no creeping. The Z axis with the screened cable does not suffer from the creep problem. I then replaced the X & Y axis with screened cable to match the Z.... - this upgrade to the X & Y cable did not fix the problem but did reduce the creeping slightly.

I then replaced the limit switch wire with screened cable similar to the X Y & Z axis. I only had enough screened cable to do between the control box and to a corner of the table where I branch in 2 directions with normal un-screened cable to the limit switches. I will get more cable this week.... Adding this screened cable did not stop the creeping - but the amount of creep has increased to be similar to before adding the screened cable to the X and Y axis.....
 
OK, after testing different procedures, I found something interesting.... With the control box live, running the spindle motor there is no creeping on the X & Y axis - but when I switch on the PC and the PC configures the printer port (cable between the PC and the control box), the X and Y axis start to play up again. This is without running Mach3.....
Another interesting point, there is no creep when I unplug the limit switch cable from the control box. This is the same for the partially screened cable and no screen on the limit switch cable. Remembering that the system was running perfectly before replacing any un-screened cables with screened cables.....

I am scratching my head now - I do not know what to try next to eliminate the X and Y creep... Anyone have any ideas on what I can try next? I could try to remove all screened cables - I really do not want to do this - adding screened cables should not be a negative feature - but is should be a worthwhile upgrade...

Pages: 1