Turn on a switch, light a lamp

Getting the lesson ready…

A switch, a lamp and the small computer between them. Three words: PLC, tag and scan.

Turn on a switch, light a lamp: the words you will learn

the small computer that runs a machine

PLC

the name the PLC knows a part by, such as Switch or Lamp

tag

one read of the PLC's rules, about 50 times every second

scan

the list of rules the PLC follows

program