On 2013-09-17, Lloyd E. Sponenburgh lloydspinsidemindspring.com wrote:
BQ340 fired this volley in news:523799df$0$63180
:

no plug-reversing motors with VFD's for one

That's a matter of planning, rather than a specific advantage or
disadvantage. The application matters.

VFD's decelerate then re-accelerate when switch-reversed.

RPCs do it more rapidly, but NOT instantly, which might be wanted in some
applications. They also severely stress everything while doing it.

And if you plug reverse a big enough motor with a big enough inertia,
it may happen that the motor will keep the rotation, but the phase
converter idler willr everse.

i