Well, this certainly has not been the best of days 🙁 … I was slowly milling into a steel bolt/a cast iron base with my 2.2 kW spindle and 2.2 kW Huanyang VFD, and I seem to have damaged either the spindle motor or the VFD unit … During the steel bolt/cast iron milling I happened to lower the Z-axis a little bit too quickly (although not very quickly) and this slightly halted the motor for a moment – but not at all to a stop.
However, normally the VFD accelerates the motor gradually while generating a motor sound with a slowly increasing frequency, yet after this steel/cast iron milling this sound is suddenly completely changed (??) .. I have attached a short sound recording to this post where this new sound can be heard during motor accelleration and deceleration.
Also, it seems that the motor now vibrates slightly in a "thud-like" manner as if the VFD power is applied sort of in an uncoordinated manner.
In order to try to assess if the spindle motor itself has been damaged I have rotated the spindle by hand so as to maybe feel if there could be a damaged bearing but it does not appear to be the case. The spindle appears to rotate freely without any "grits" or the like during rotation. Also no grit sound.
I wonder, however, if this steel/cast iron milling somehow may:
1. Either have caused a current surge in the VFD which have damaged the VFD’s output circuitry, or
2. Maybe a power drop inside the VFD which may somehow have damaged the internal settings or ?? in the VFD?
Might I be so lucky that someone here knows about what this could be, and may suggest a remedy? I use the CNC mill almost daily so it really is a setback that this has happened … I would much appreciate help here …
With many thanks,