forum.cncdrive.com

Hello,

can the VFD "read" the actual frequency/speed/rpm of the spindle. As an example - I setup the speed to 6000rpm, the display shows the corresponding Frequency (100Hz) - but lets assume that something exerts the braking force on the spindle (with hand/or just cutting heavily in a material) and the ACTUAL rpm/speed is lower than the one which was setup. Can the VFD show it? or it will only display the "expected" value? and to get the real frequency/speed of the spindle I would need an external tachometer?

The question is important for "wait for spindle" function - it needs to check if the spindle is REALLY working and not just pretend (or was blocked).

Thanks.

This Response is a little late,
Depending on your VFD you should be able to display RPM.
What VFD are you working with?

China inverter SKI780

Ok So reading the manual Page 33 Your VFD does not offer the ability to display rpm, Only frequency(HZ)
Hope this helps.

The problem is not in displaying the target frequency/rpm (doesnt matter - you can always recalculate it) - the problem is to display „real” rpm/frequency.

You can set it to display frequency just not rpm.

Page 33 in the manual shows what setting does that.