Re: rod-mill project - "mains" electric motor advice

On 31/05/2025 10:15, Richard Smith wrote:

Joe Gwinn <joegwinn@comcast.net> writes:
>

On Fri, 30 May 2025 12:47:04 +0100, David Billington <djb@invalid.com>
wrote:
>

On 30/05/2025 10:10, Richard Smith wrote:

That bit of "headroom" "saved the day".
(the device, the VFD, refuses to go above 60Hz output - likely don't
want "the heat" from people turning up at hospital with bits of motor
embedded in them?)

In my limited experience with 2 VFDs they come with a default maximum
output frequency, 50Hz IIRC with mine, which you have to change in the
configuration if you want to run faster. The first ABB VFD was changed
to 100Hz, the 2nd a Chinese one to 400Hz. RTFM.

This is my experience too.
>
Joe

50% faster would generally be without unsought thrills?
>
YOu could go a bit faster as a test with everything out of the way, then
settle on what you want?

The ABB VFD I was using was connected to an inverter rated TEFC motor, like that one you showed in your clip, and rated to operate at up to 2X the nominal speed at 50Hz, it was powering a flat lap for glass and V belt speed reduction to the lap platter. I only had to balance it slightly to have it run smoothly from min to max speed and no drama even at resonant speeds before balancing. Nice feature of the VFD was scaling of the output display so I had it display platter speed rather than motor speed.
The Chinese VFD set to 400Hz was powering a 24k rpm spindle which is what it was supplied for but it came with basic default parameters so it had to be programmed to run up to 24k rather than 3k so I configured it to run from the VFD panel as a basic test of the VFD and spindle, next is to change the settings for external run input and 0-10V speed control.
What happens if you run things faster in your application you'll have to assess with the components you're using.