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   rec.crafts.metalworking      Metal working and metallurgy      215,367 messages   

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   Message 214,395 of 215,367   
   David Billington to Richard Smith   
   Re: rod-mill project - "mains" electric    
   31 May 25 14:35:43   
   
   From: djb@invalid.com   
      
   On 31/05/2025 10:15, Richard Smith wrote:   
   > Joe Gwinn  writes:   
   >   
   >> On Fri, 30 May 2025 12:47:04 +0100, David Billington    
   >> 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.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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