In article ,
wrote:

By its very nature a vfd can be configured to "soft start" as one of many
selectable parameters. Most old motors weren't designed for vid operation
but many of them are ok so long as their insulation has not become too
degraded over time.

Bob Swinney

wrote in message
...

On Mar 3, 9:36 am, "Oppie" wrote:

Was thinking of adding a soft start system in series with the original
starter. Considered a VFD but have heard that using one with a motor not
designed for such makes problems. Even adding a line reactor to remove
harmonic content may be required. All told, a soft starter appears to be
the
best choice.

Oppie


You might ask if there is anyone that has had problems using a vfd on
an old motor. I know it is possible to have a problem, but I have not
had a problem. However I have not used that many VFD's with old
motors. So I would ask others with more experience.

I think what saves us using old motors on VFDs is that most HSMs use 220
volt single phase feeds, and the motors were built for dual-voltage,
typically 220/440, and so have stout insulation.


Joe Gwinn