ABB S200-OE4 PLC

Electro Electronics Repairs does repairs on any brand of PLC

A Programmable Logic Controller, or PLC, is a ruggedized computer used for industrial automation. These controllers can automate a specific process, machine function, or even an entire production line.

A Programmable Logic Controller consists of various input and output terminals. Using the input terminals, it interprets the logical states of switches and sensors. There are two logical states: high (or 1) and low(or 0). The output from the output terminals is used as a signal for various devices, providing them on/off controls. The electrical engineers understand the ladder logic diagrams, and so it was the inspiration behind the programming language used to program it.

PLCs operate in cycles. First, the PLC detects the state of all input devices that are connected to it. The PLC applies the user-created logic, and then executes it based on the input states. The PLC then outputs commands to any output device connected to the PLC either turning them on or off. After completing all these steps, the PLC does a safety check by communicating with internal diagnostics and programming terminals, to ensure that everything is within normal operating conditions. The PLC resumes the cycle each time the process is completed.