PLC Switch Actuation Status

Determine the necessary PLC switch actuation status (i.e. low versus high process stimulus) to turn the yellow lamp on.

Example PLC Program

A PLC has been programming to control the starting and stopping of a three-phase electric motor.

PLC Program to Control a Water Pump

PLC program to control a water pump driven by an electric motor. It will be manually started and stopped by pushbutton switches, and shut down automatically by any one of several “permissive” switches.

PLC Practice Questions

Explain what the following PLC Practice Questions on “ladder-logic” circuit does, and identify the meaning of each symbol in the diagram: PLC