View Full Version : Problem Limit switches tripping on PRO4896

11-09-2015, 07:21 PM
I have a new issue that has reared its ugly head over the last week.

The issue is that Mach3 states the limit switches are tripping when in the middle of a job. The router is nowhere near a switch. When I check the indicators none of them are tripped either. That goes for software and hardware indicators.

All I have to do is hit the reset button in the software and its cleared. The odd thing is that if I rerun the job, it will go up to just a little past where it stopped the last time and then trip again.

Is this hardware or a setting in Mach 3 that needs to change?



11-09-2015, 11:16 PM
I did some serious googling tonight and found some suggestions to turn on noise filtering in the speed stepper config.

A couple of threads seemed to conflict one another on what the optimal setting should be. One said to go low using 1.43 as the setting that solved the problem there. However, another thread said they resolved their issue with a setting of 500.

I punched in 5 as a starting point and didn't improve. I decided to go roughly halfway and used 200. I ran a shorter job (20 minutes) and it finished without issue. Before, it was stopping at 2 minutes for the first try and then 45 seconds longer each iteration afterward. Meaning it would carve uncarved wood for 45 seconds and then trigger the switch.

I have more carving to do tomorrow and will monitor and see if it comes back.


11-10-2015, 03:45 AM
What type of electronics do you have on it?

11-10-2015, 09:55 AM
I also had a similar problem to this, make sure all the connections are screwed on tight to the switches themselves. I had one connection that had started to come loose from vibration and it would randomly trip the limit, but wouldn't show up in Mach 3.

11-14-2015, 11:11 PM
Good advice from MobiusConcepts on checking the sensor connections - I'd also suggest taking a look at the ethernet cable, a loose ethernet cable (ie. a cable with a broken or ineffectual tab at either end) can cause a similar condition as well, driven by either vibration or changing tension on the cable.