random stalling

[ihavenofish]

so, i got a mill here that uses a cnc4pc break out board with gecko g203v drives and nema43 motors.

im getting random stalling as a program runs. x and y in random places. z does not seem to stall, though the programs have only small incremental z motions.

i had random stalls on my g540 at one point, and tuned them out using pulse timing in the motor tuning settings in mach. on the g203 machine, i cant seem to get rid of them. ive tried every kernel speed, every pulse setting, speed, acceleration etc. tried sheline mode as well. sometimes it will go many hours/days of running with no stalls, then stall every 5 minutes.

at this point i have only a few more thoughts:

1- possibly flakey power? would unstable power cause soemthing like this? the las bout of bad stalls was during a rain storm and the building is know for not having the best power. i know computers are very fault tolerant on power, but maybe the gecko isnt?

2- bad pc. doesnt seem to be using 100% cpu, but maybe its not liking the paralel config. this is a coputer used in all of this suppliers machines which report very few issues.

thats all i got at this point. anyone have any other ideas?

[ihavenofish]

so, hooked up a shiny new pc to the machine tonight.

i tested it on my g540 first, and it seemed to work perfect - only ran it for an hour or so though and all my programs were 500 line limited due to demo mode in mach.

on the big machine, i just copied over the old xml and changed the kernel back to 25k and the pulse timings to 2/2. basically default. seemed to work ok, though the pci express parallel card likes to lose connection once in a while and force an E-stop.

i did check the mach3 driver test and the new pc has a smoother spike free pulse stream. both rate "excellent" though.

i played with settings some more, and managed to get the machine cruising at 175ipm, something the old pc wouldnt do at any setting. ran a few programs, jogged, all was well.

ran my "problem" program and it would stall in a similar spot in the program each time - not random. must be hitting just the right spot and speed to do it cause jogging past that spot has no issues. so i set it all back to the normal 100ipm and it was fine again.

so, out of curiousity i reconnected the old pc and reset the settings the same as the new, and it ran through the "problem" program stall free. it was "noisier" whe running though. only had time to run it once though so it may have been a fluke.

so basically new pc is definitely better, but im not sure yet if its the solution.


also for reference the bytecc pci express 2 port parallel is probabaly not a good choice.

[ihavenofish]

i know noone cares, but the problem did turn out to be the old PC. i swapped out parallel cards in the new one to the single port pci express one in the old machine and its flawless now. i also thing the dual port parallel card is likely good, but it forced me to use the default MS drivers. the single port card came with its own drivers.

[ger21]

It seems to me that the majority of these types of problems that people see with Gecko's (Especially the G540) are due to the PC, or more specifically the parallel port.

[ihavenofish]

Originally Posted by ger21 It seems to me that the majority of these types of problems that people see with Gecko's (Especially the G540) are due to the PC, or more specifically the parallel port.

this one wasnt the port, just the pc. i really cant imagine why the old pc is bad though. the guys that made the mill say they use the same pc on every machine, and every once in a while one just doesnt work right.

[2ferrous]

I was having similar problems with my G540 powered mill. I tried switching ports, reinstalling PCI drivers and even installing a buffer board. Slowing down the stepper motor speed and acceleration helped but it was still losing steps and stalling at random times.

I ended up removing the PCI cards and installing a Smooth Stepper. I also found out I have poor power delivery to the shop so I added a UPS to the computer cabinet. A power conditioner will be installed in the future just to be extra safe.

All the problems were PC based. The Gecko G540 has/is working flawlessly.

Timothy