You will encounter two types of ladder diagrams: the 2-wire control circuit and the 3-wire control circuit. The 2-wire control circuit is shown in Fig. 2. This circuit is used to start a motor for ...

And, the ability to monitor PLC logic in ladder diagram format also made troubleshooting easier for those already familiar with relay-based control systems. Although there are many higher-level ...

Rather than the classic “contact and coil” representation of ladder diagram or relay ladder logic programming, function blocks present a graphical image to the programmer with underlying algorithms ...