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Re: Acorn controller card question

Posted: Fri Mar 19, 2021 8:20 pm
by martyscncgarage
noel-nogal wrote: Fri Mar 19, 2021 8:11 pm that helps a lot, it's very good information, it mean in both cases closed loop will keep machine accurate, and also any error that the drive can't fix or keep up will stop the movement. i understand now, actually i have a small cnc with leadshine closed loop stepper motors and i think they work the same way, they are running with deskcnc controller.

thank you so much, it is very clear to me now.
Glad it helped a bit.
Yes, same idea with your smaller machine.
Marty

Re: Acorn controller card question

Posted: Fri Mar 19, 2021 9:11 pm
by tblough
With a full closed loop controller, you can turn the motors off and run the machine just like a manual machine and then turn the motors back on to do CNC machining. On a lathe, you can have dual handwheels to control the carriage and crossslide to perform manual machining. Manual control is not possible with the Acorn.

Re: Acorn controller card question

Posted: Sat Mar 20, 2021 8:58 am
by Richards
Marty explained things perfectly about Acorn vs Oak. One thing to keep in mind is that if the drive/servo or drive/stepper are properly sized for the load that they are expected to drive, and if the speeds used do not overdrive the motors, the drivers will not fault.

On an open-loop stepper system, there is no feedback from the drive to the acorn. If an open-loop stepper faults, it just stops.

On the Acorn with the drives/servos that I've used (ClearPath and DMM/DYN4), the drives send out a fault signal when they cannot handle the load/speed that the operator programmed in G-code. If the drives/servos are properly sized, they won't fault.

The bottom line for me is that if drives/motors are selected that can handle the loads expected, the Acorn does an excellent job. On the other hand, if the Oak were used, and the drives/servos constantly faulted. The Oak would know the servo's position; but, the fact that the servo constantly faulted indicats that the servo is too small for the job or that the operator set the feed rats too high in his G-code.

Re: Acorn controller card question

Posted: Sat Mar 27, 2021 3:01 pm
by noel-nogal
thank you guys.

i have an other question, i am doing the bench test and i noted taht the relay output 2 vary its voltage when i adjust the spindle speed buttons, actually i can see its led turn its color red to green slowly and the relay start to buzz when voltage drops. how can i fix this

Re: Acorn controller card question

Posted: Sat Mar 27, 2021 3:11 pm
by martyscncgarage
noel-nogal wrote: Sat Mar 27, 2021 3:01 pm thank you guys.

i have an other question, i am doing the bench test and i noted taht the relay output 2 vary its voltage when i adjust the spindle speed buttons, actually i can see its led turn its color red to green slowly and the relay start to buzz when voltage drops. how can i fix this
Did you enable PWM by chance in the Wizard?

Re: Acorn controller card question

Posted: Sat Mar 27, 2021 3:22 pm
by noel-nogal
yes, i did, i fixed it already, thanks, i still have lot to read and learn.

have a nice weekend

Re: Acorn controller card question

Posted: Sat Mar 27, 2021 4:35 pm
by martyscncgarage
PWM output is via Output 2 on the DB25. When it's used, for the time being you can't use Output 2 on the relay board and its line should be cut.

But now you know....

Re: Acorn controller card question

Posted: Sun Mar 28, 2021 3:14 pm
by cbb1962
I have an Acorn controller on a Router with Yaskawa Servopack SGDM-10ADA-V and SGMGH-09ACA61 Servo Motors I've never experienced lost steps. But I have lost communications with the Acorn during a run before, I simply re-homed and continued the job. I too considered going with an Oak board, but ultimately went with the Acorn I used these Yaskawa connectors and this adapter board for the Acorn from CNC4PC. It greatly simplified the wiring since this uses ethernet cables. Here is a sample wiring diagram.

Re: Acorn controller card question

Posted: Wed Mar 31, 2021 6:19 pm
by noel-nogal
Hello

i am trying to find the arrow esc button on the left bottom corner of the screen, it don't shows up, do you know where i can find it?

thanks

Re: Acorn controller card question

Posted: Wed Mar 31, 2021 6:32 pm
by noel-nogal
thanks Clint.

i already have the acorn controller, i am doing bench test and learning, i also keep studing the yaskawa servo drives to start making connections, i will look at these connectors you mentioned above.