I haven't used Hitachi, but I use the equivalent in Mitsubishi, including the encoder feedback type, which are even better when you want accurate rpm control.
A VFD can be just variable speed or torque/vector control where the torque is attempted to be maintained across the speed range. You get what you pay for.
Al.
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CNC, Mechatronics Integration and Machine Design.
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E. |