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 ...

Comprising a base terminal block and pluggable relay, the CWRE 6.2-mm-wide PLC relay interface is rated for ac and dc circuits and suits all types of inductive applications. The relay interface comes ...

The PuffinPLC Project is an effort to produce a Linux-based GNU Public Licensed Programmable Logic Controller (PLC). PLCs were developed in the 1960s to replace the complex electrical relay circuits ...

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 ...

In part one of this series, we looked at the PLC’s internal architecture, briefly discussed Ladder Logic programming, Human-Machine Interfaces, advantages of the PLC’s ability to react consistently ...