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 ...

The programmable logic controller (PLC) is a microprocessor-based system that accepts input data from switches and sensors, processes that data by making decisions in accordance with a stored program, ...

When learning ladder logic, I was told that some new PLC systems were moving to scripted programming languages. My instructor assured us that we would not need to know anything other than ladder logic ...

In this column, we take a closer look as to how timing and delays affect our logic circuits. As part of this, we start to consider the timing diagrams presented in data sheets. As I was writing my ...