The major concern is if the existing motor is suitable to be fed off a VSD to begin with.
There's the problems of insulation and increased temperature rise, high dv/dt values damaging insulation and causing PD, and bearing currents causing discharge machining.
Retrofitting the existing motor...
Is a weldolet/weldneck flange combination preferable to a sockolet/nipple/socketweld flange combination when providing a piping connection for a flanged thermowell? Does connection strength come into play? Assume that thermowell O.D. and insertion length are variable as required and that piping...