With the limit and home switches set up and homing etc configured, it seemed a good time to test the VFD installation. I'd wired this up last year when I built the cabinet and rather pleasingly it seems to work out of the box. Just needed to go in and set the motor parameters etc and the job's a good 'un. The TEC motor seems to make a good loudspeaker using the default settings, so I set the carrier (switching) frequency to the highest setting (12kHz?) which pretty much makes it ultrasonic for old gits like me. There's a nice squeak when first enabled but the carrier frequency rapidly rises to a more pleasant place.
With these VFDs, you can develop full torque at stall (0rpm), notwithstanding the thermal limitation on extended operation which I believe is protected by the default thermal model inside the VFD. But for the kind of slow speed operations I'd expect to be doing (tapping and drilling), that's unlikely to be an issue. In the limit (so to speak), it would be possible to either change the thermal parameters for the motor, use the built-in motor thermistor for feedback of the actual winding temperature (yes, there is one) or ultimately fit a static fan to genuinely extend the thermal envelope. Really not an issue for me....
Love these Yaskawa drives!
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