Machsupport Forum
Mach Discussion => Mach4 General Discussion => Topic started by: irakandjii on April 09, 2019, 09:43:08 PM
-
Hi I am new to mach4. I just got my motors running and went to tune the motors as told on the manual.
I cannot enter values into the boxes, they are greyed out. Any hints on what I should do?
-
You must click on one of the Motors in the column at the right
to highlight the selected motor before the boxes can be edited.
-
Yes I have done that I select motor 0, which is the one I want to tune
-
Ahh ok, I thought the check mark was good enough I get it now tyvm
-
Hi I am new to mach4. I just got my motors running and went to tune the motors as told on the manual.
I cannot enter values into the boxes, they are greyed out. Any hints on what I should do?
Which brand and model of Motion Controller are you using?
The correct setup of the plugin of the motion controller must have been done and link mapped correctly before MACH4 can tune motors.
-
I am using a PoKeys57CNC with Mach4 plugins.
I am in the process of first set-up. The stepper is stuttering badly.
I am trying to diagnose the problem.
I got tuning to work. I have yet to determine the best settings. Right now even at 60 rpm the motor stutters.
-
Hi,
there was a post a while back where a guy had problems with a 57CNC. It gave the symptoms of having insufficient
kernel speed despite apparently being within spec. If memory serves he ended up getting an ESS which has a max pulse
rate of 4MHz, compared to about 100-125kHz for the 57CNC.
What microstepping regime are you using?.
I would suggest that anything over 8 microsteps per full step (1600 pulse/rev) is unwarranted. Higher regimes offer no
more resolution, I now that sounds contrary to common sense, and I will explain if you absolutely require, but trust me
you get no higher resolution beyond 1/2 step. While higher regimes may offer somewhat more smoothness a regime
of 8 microsteps already offers a good improvement in that regard.
The principle problem with higher microstepping regimes is that for a given rotational speed the number of pulses required to
do one revolution goes up. Therefore your controller CPU/FPGA/DSP has to work that much faster. From what you have described
I think you may be trying to push the 57CNC at or close to its limits which may describe the stuttering.
Craig
-
Hi Craig
I Have tried 400 - 6400 microsteps all produce the same stuttering. I have reset to 800.
I have adjusted max speed from 50 to 250 rev/min - same stutter
I have adjusted max acceleration from 2 to 10 rev/sec2 - same stutter
I am going to try a different computer now
Note:
PoKeys57CNC outputs 5V with max 8 mA on the logic circuits
The Leadshine Stepper drivers need 7 mA min with 10 mA typical
I suspect I need to amplify the logic leads out of the leadshine, I just forget how to do this lol
-
Hi,
well you've certainly experimented enough. I'm thinking like you that maybe the PC is stuttering.
I use an ESS and Warp9 definitely recommend that WIFI and any other Ethernet adapter be disabled on
the PC that runs Mach. It might be worth checking that you have no competing comms going on.
Craig
-
Success!!!
The stuttering was caused by the USB 3.1-USB 2.0 interface between the PoKeys57CNC and the computers.
I converted to ethernet and all stuttering is now gone, on to the next phase!
Thanks to all that helped!!
-
"I converted to ethernet and all stuttering is now gone"
EXPECTED if one understands the technologies.
ADVISE To all others
Upgrade from MACH3+Parallel port to MACH4+Ethernet Motion Controller
Avoid ALL USB motion controllers.
-
Hi,
I too prefer Ethernet however PMDX have quite a history with their Mach4 capable smart BoB's, all USB connected
and without apparent difficulty.
I am less certain that one is better than another but rather the care with which each is implemented. USB seems to
be more sensitive to how it is enacted but PMDX have had a pretty good run with it.
Craig
-
Even PMDX is going ethenet with the PMDX-426.
(Warp9) USS - USB obsolete - no plugin for MACH4
(CNCDRIVE) UC300 - USB version website says Obsolete - NO MORE IN PRODUCTION
Ethernet
or usb with troubles - will need USB Isolation Earth Device Device + Ferrite sleeves as BAND-AIDS.
-
Sorry, but the PMDX-426 project was put on hold because we found USB to work well.
USB is not quite as resistant to noise as Ethernet, but latency and speed are not
issues with Mach4. There can be issues if you plug in a large USB storage device
and Windows goes away while it caches directories, but this problem affects any
system, including Ethernet ones, because it is related to Windows behavior not to
the communications between Mach4 and the motion device.
All of our SmartBOBs employ common mode noise filtering on the USB port, and the
PMDX-424 (and other products being considered) employ electrical isolation to
break potential ground loops between the machine controller and the host PC.
For table top machines, and many larger machines things work well without
ground loop problems, but for industrial machines we do recommend using a
controller with isolation.
Twisted pair Ethernet (10BaseT) uses transformers for electrical isolation and
this prevents ground loops.
We chose to continue with USB because we feel that it works well for us and
because USB configuration is dead simple. Ethernet and IP addressing is normally
simple except when it isn't, then there is hell to pay in doing tech support for it.
-
Hi,
thanks for the clarification Steve. It supports my contention that USB when well enacted works fine
notwithstanding its somewhat weaker specs.
I think the reason that USB has gotten a tarnished reputation is because a lot of manufacturers have made cheap
USB solutions and those have been problematic. This is more about poor design/build quality than it is about
the limitations or otherwise of USB.
Craig
-
Sorry, but the PMDX-426 project was put on hold because we found USB to work well.
My apologies.
Attached picture is example of USB ground loop isolation devise. Requires external 5V PSU.