Dear all, I am using the Blackbox to control a AMB (Kress) 1400 FME-P DI. It is wired up to use the 10v analog signal to control spindle speed. It is wired like shown here (this should ensure my ground is proper). It works, sort of, and I can have the spindle run at different speeds. However, I cannot trust the voltage/rpm. Given it is 0-10v I would expect 100% speed to give 10v, 50% to give 5v, 25% to 2.5v, 10% to 1v etc. I can adjust the max output (10v/100%) through the 10v trimmer on the Blackbox, but not the other values. I am getting these readouts at the spindle: 100% speed - 10.5v 50% speed - 4.45v 25% speed - 1.42v 10% speed - 0.139v According to the documentation of the AMD 1400 FME-P DI, the spindle speed is 0 from 0-1v, 3500rpm (minimum) at 1v, 25000rpm at 9-10v. It is linear from 1-9v as documented here. I need input/suggestions on how to calibrate/adjust the Blackbox 10v control signal to actually be linear and reliable. I would like to be able to enter eg. 12000rpm in my gcode and actually get 12000rpm. Cheers Martin
The linearity is not adjustable, but should be fairly accurate - at least good enough for the use case. You won't notice the difference between commanded and actual RPMs on a Kress spindle (it will even vary during the cut as the load changes through the cuts)
Hi Peter. Thank you for your quick reply. I don't think the voltages I am getting are fairly accurate. Do you believe they are within acceptable limits? 10% giving 0.139v is way off I think, as I would expect it to be 10v.
