Centroid Community CNC Support Forum

I have been trying to get my spindle speed to match what is on my screen or to be exact the screen to read what my spindle is turning. I downloaded what Keith had posted in another post (Acorn VFD Frequency calibration.pdf) I have been messing with the Max Hz and nothing is changing. Max spindle rpms is 5600 and minimum is 650 set on high. This is a pully style Mill in the pictures I have a chart from the original manufacture according to the PDF it says to command the spindle to 1/3 the maximum speed which would be 1867rpms while it's running it says to adjust the maximum Hz so the spindle turns at the correct rpms. Well that doesn't do anything the spindle stays a constant 2678rpms if I increase the speed to achieve my max rpms the screen posts 4144rpms but the spindle is turning 5675rpms. I know it's something stupid I'm overlooking and this is where you people double check my stuff. Oh by the way the picture of the screen wizzard is wrong I changed the minimum to 650rpms

John

https://photos.app.goo.gl/TDd6Uhr1urc3mbLBA

How are you measuring the spindle RPM? According to your report, you do not have a spindle encoder. Therefore, the displayed rpm on the CNC12 screen is the commanded RPM and not the actual RPM. It will not change until you request a different RPM. You will need to use some sort of tachometer to determine the actual spindle RPM.

On your VFD what is the value of P05? P23? P24? P45 and P46?

Yes, I'm using a Tachometer.
P05 = 3
p23 = 0.0
p24 = 60.0
p45 = 0.0
p46 = 80.0

I knew someone would smarten me up, I totally missed p46 set that to 60.0 and now it reads correct. Well within38rpms
Thank you Tom