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 ...

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 ...

Some control applications are too small or simple to use even the smallest PLC, but still need more flexibility than a simple relay. That's why engineers at Schneider Electric, Palatine, Ill.

There are various approaches to developing programmable logic controller (PLC) applications using experimental techniques. Modifying existing PLC ladder logic programs is another common approach ...

In the first two installments of this series, we discussed whether or not an old transmitter was even worth fixing, followed by some techniques I ve used to repair high-voltage power supplies. This ...

Most industrial facilities include electric motors that require overload relays for protection, control and monitoring purposes. The latest overload relays are often called motor management relays ...

On the surface, a programmable logic controller (PLC) might seem like nothing more than a generic microcontroller, perhaps outfitted to operate in industrial settings with things like high ...