Single-phase and 3-phase AC squirrel cage induction motors need some type of control circuit to initiate a start or stop function. The two types of ladder control circuits commonly used are the 2-wire ...

In Part 1 of this two-part series, we presented a 3-phase, 480VAC motor circuit with its associated controls (Figure). We stepped through a logical, systematic approach to troubleshoot the main power ...

Guest columnist Alfred Hesener, European marketing director at Fairchild Semiconductor, describes how good design of power switches can help reduce losses in motor control circuits. Energy-saving ...

The circuit in the figure provides three levels of speed control for a dc motor, using a PC’s parallel port (LPT1). A C++ program performs the control functions by allowing the signals from the PC ...