When a PLC is used primarily to replace relays, timers, and counters, it's hard to beat the simplicity and usefulness of ladder diagram programming. Their ability to accept programming in ladder ...

Ladder logic uses switch or relay contacts to implement Boolean expressions. In years past, ladder logic was made possible with discrete relays and was sometimes termed “relay logic.” Today most ...

Abstract: Programmable controllers (PLCs) were developed to solve the problems of automating and manufacturing control systems and they have found wide applications in industrial control fields.