Quote Originally Posted by kwired View Post
I installed one one time that does run loaded at low speeds, we used an inverter duty motor with additional electric fan for cooling it.

When first put that machine on VFD it burned out a motor about once a year, we had a spare motor so swapped and had other rewound. After about 4th time we got the VFD rated, external fan cooled motor, and has ran for maybe 10-12 years now. Bearing has gone out on cooling fan, but careful selection of motor overload has caught it. Wired so drive won't give a run command if cooling fan isn't running.
Just put one in on the 4th. Hopefully it lasts more than 1 year. It will help that after re-checking cooling fan rotation (initially checked by installing mechs.) it was going backwards. Did a similar hard-wired stop with the fan