A programmable logic controller (PLC) or programmable controller is an industrial computer that is durable and adapted to control production processes such as assembly lines, machines, robotic devices, or any activity that requires high reliability, easy programming, and diagnosis of process errors. Dick Morley is considered the father of the PLC, as he invented the first PLC, the Modicum 084, for General Motors in 1968.
PLC programming software
The PLC program is usually written on a computer and then downloaded to the controller Most PLC programming software offers to program in Ladder Logic. Ladder Logic is a traditional programming language. It mimics circuit diagrams with logic "bars" read from left to right. Each rung represents a specific action controlled by the PLC, starting with an input or series of inputs (contacts) resulting in an output (coil). Due to its visual nature, Ladder Logic can be easier to implement than many other programming languages. C programming is a more recent innovation.
PLC manufacturers supply control programming
Some PLC manufacturers supply control programming software. Unitrans now offers several rugged PLC product lines to support a wide range of system requirements. These compact, game-changing controllers create immediate savings by eliminating time-consuming tasks such as PLC-Panel wiring and communications setup. Unitrans supports the All-in-One concept with revolutionary software that has enabled Ladder control programming, HMI design, and all hardware configuration and communication in one simple software environment.
Ladder Logic or "C"
Most PLC programming software offers to program in Ladder Logic or "C". Ladder Logic is a traditional programming language. It mimics circuit diagrams with logic "bars" read from left to right. Each rung represents a specific action controlled by the PLC, starting with an input or series of inputs (contacts) resulting in an output (coil). Due to its visual nature, Ladder Logic can be easier to implement than many other programming languages.
Sensors or input devices
A PLC receives information from connected sensors or input devices, processes the data, and triggers outputs based on pre-programmed parameters. Depending on the inputs and outputs, the PLC can monitor and record operational data such as machine productivity or operating temperature, automatically start and stop processes, generate alarms in case of machine failure, and more.
Electromechanical relays
Programmable Logic Controllers are a flexible and robust control solution that can be adapted to almost any application. Other engineering firms developed their own versions of this device, and it eventually became known in non-proprietary terms as a PLC or programmable logic controller. The purpose of the PLC was to directly replace electromechanical relays as logic elements and instead replace the solid-state digital computer with a stored program capable of emulating the interconnection of many relays to perform certain logic tasks.
Ladder logic diagrams
Programmable logic controllers (PLCs) were developed in the 1970s to replace hard-wired relay logic. They can be programmed using the same ladder logic diagrams or other textual and graphical programming languages to represent logic, and are an excellent tool for implementing discrete logic. Lyskills provides PLC boot camp training courses in Lahore. PLC manufacturers provide robust, cost-effective discrete I/O modules that can scan discrete data points (sensors) very quickly. Scan speeds much faster than 100ms are common.