forum.cncdrive.com

Hi, making progress on my changeover to the AXBB-E from the UC400eth. Ran into a bit of a problem running the spindle. I'm suspecting noise but it's a little bit too consistent to confirm that. I'm attaching a photo that shows the analog input for my vfd. And another photo showing the connection diagram in the AXBB manual. Can anyone help with the proper connections for those two devices? the vfd speed control is configured to work with 0 to 10 volt. I have removed the jumper inside the AXBB to output 10 volt.

And second, I'm not sure what the recommended settings are for the pwm output pin and the analog channel. Does it matter what pin I assign the pwm output to? Since it just gets tied internally to the analog output of the board? What pwm frequency should I use?
So before I do any more troubleshooting I want to make sure that I have things connected the right way and configure the right way. Any help would be appreciated.

I haven't setup my AXBB-E yet, but here's my guess.
The PWM frequency is not used?
On the I/O setup page, set "Spindle PWM ->Analog Channel" to 1. The Analog Inputs and Outputs don't use port and pin numbers.

I think all you need are two wires.

AXBB >>>> VFD
AO1 >>>> AI1
5V0 >>>> GND

You also need a relay to start and stop the spindle, using the Digital Inputs on the VFD.

The PWM port/pin and PWM frequency setting does not matter if you using the analog channel. You can set them whatever you want.
The only things what matter are the PWM min and max range and the spindle speed min and max range, those set the analog voltage range and attaches it to the spindle speed range.

Thats how I had it. But I wasn't sure whether the AO references the 5V ground or the 24V ground. I was able to get it to run long enough to adjust the speed with the SRO but something is set wrong because I couldn't get the max RPM greater than about 18000.

CNCdrive: Our replies crossed. Thanks. I had forgot to set those variables. That will probably fix my speed range problem.

So, you don't have to assign the PWM output to a pin? Just link it to Analog channel 1? And pwm frequency?

It is referenced to 5V0 ground.
Yes, you do not have to set the PWM frequency and it does not matter what is the PWM port/pin if you using the analog output channel, just assign the analog channel to the spindle PWM and set the PWM min/max and the spindle speed min/max range, those will define the analog voltage range for the spindle S range.

Quick update. While trying to solve a noise problem I swapped in a different VFD. The new VFD accepted a pulse stream input as well as 0-10v for speed control. Previously the old one would only accept 0-10v. I set the right parameters and changed the software spindle speed control to step and direction from PWM. This works great. The output pins on the AXXB-E are fast enough to output the stream (~5khz to 16khz). Also, run command instead of a contact closure from a relay, is now just a -24Vdc wire from one of the AXXB-E's output. Pretty happy with the simplicity so far of the AXXB-E.

So did you have to run a relay to control the spindle?