Grigg,
You are correct, the frequency drive is hard wired to the motor, but I can't think of any thing that wouldn't be hard wired to the motor. There is no length limitation on motor or control wiring until you get into a tremendous distance between drive and motor then you stick in a line reactor.
I'm not sure what you mean about switches on the drive side and not the motor. The drive IS the switch! I'm a big fan of freq drives and have installed many of them.
Non technically speaking, the drive is the ON-OFF switch, the REVERSE switch and motor protection all rolled into one dinky little enclosure. These are a few of the things this little box can do that a phase converter (static or rotary) could never do:
Accelerate or decelerate to a ramp of your choice.
Dynamically brake the motor as fast as you want.
Jog the motor forward or reverse.
Protect the motor from over current.
Instant reversing with accel/decel ramps.
And last but not least, variable speed from 0 HZ clear up to 400 HZ all with the turn of a simple potentiometer.
Phase converters work well but they are very dumb, need a magnetic contactor or drum switch and require additional motor protection.
I too have both types of controls. The dumb one is on the table saw, the smart ones are on the drill press, lathe and mill.
Stuart
