Energy Efficiency

Energy Efficiency January 1, 1970

Sensorless AC Drives Fill Price/Performance Niche

KEY WORDSMotors, drives, & motion controlAC variable-speed drivesAC induction motorsAdaptive controlControversial right from their name, "sensorless" ac drives actually use current and voltage sensors to achieve motor control. Even beyond terminology, it's not obvious what sensorless ac drives can or can't do, and where they fit into the big picture.

By Frank J. Bartos, CONTROL ENGINERING
Energy Efficiency January 1, 1970

Pressure Sensing: It’s Everywhere!

KEY WORDS Process control and instrumentation Process sensing Pressure sensing One of the most-used sensors, pressure instrumentation is found nearly everywhere now. The old process standby is still there—chemical change-of-state monitoring still requires tracking such mundane variables as pressure and temperature—but it now can be found, however tiny, in manufactured goods from au...

By Dick Johnson, CONTROL ENGINEERING