In contrast to alternating current, or AC, which, depending on the supply's frequency, switches direction 50 or 60 times per second, the current in DC circuits flows only in one direction.

The 4-20 mA circuit is widely used in many monitoring and control circuits. ... Since the 4-20 mA loop is a DC current, there is another often overlooked reliability concern: moisture. All epoxy ...

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 ...

Originally published in the August 18, 1988, issue of EDN. The control circuit in Figure 1a allows you to manually adjust the power delivered to a load. By changing the setting of potentiometer R 3, ...

Prior knowledge needed: ECEA 5340 Sensors and Sensor Circuit Design. Learning Outcomes. Understand how to specify the proper AC or DC motor for a machine design. Integrate the motor to a machine, ...