Prior to the advent of the adjustable-speed drive (ASD), the polyphase induction motor operated as a constant-speed motor. Figure 1 shows the well-known torque and current curves versus speed for the ...

Courtesy of www.MikeHolt.com All questions and answers are based on the 2020 NEC. Q. What is the Code definition of “electronically protected” as related to motors? A. The NEC defines an ...

Single- and three-phase alternating current (AC) motor speed can be controlled by controlling the frequency of the voltage coming to it. Motor speed has a lot to do with the capacity of refrigeration ...

Exelon Nuclear recently replaced the original motor-generator sets for its boiling water reactor (BWR) recirculation pumps at its Quad Cities Generating Station Unit 1 with adjustable-speed drives. We ...

Arkansas-based Baldor Electric Co. launched a new direct drive technology for the cooling tower industry that improves reliability, reduces maintenance, runs quieter, and saves energy. The Adjustable ...

Adjustable-frequency drives have been billed as an energy efficient way to drive three-phase ac induction motors. Nevertheless, designers should understand that motors fed by inverter power experience ...

The line of adjustable-speed drives provide accurate and repeatable speed settings and can be used as a prime mover connected to a motor, or as a secondary drive The line of adjustable-speed drives ...

The Eon 42 variable-speed, constant-torque motor is designed for direct-drive blower applications such as fan coils, kitchen ventilators, air curtains, and unit heaters/coolers. According to the ...

What is a variable frequency drive? Heating, ventilation, and air conditioning systems' air supply used to be constant volume into a space. Now a variable air volume control is being used to provide ...

Variable speed motor controllers regulate the speed and/or torque of asynchronous motors. Depending on the application, there are controllers from a few hundred Watts up to several hundred Kilowatts.

ON Semiconductor has introduced a motor development kit for motors up to 4kW, and soon to 10kW. “In order to improve efficiency, ac induction motor drives designers must understand how these and other ...