Please enable JavaScript.
Coggle requires JavaScript to display documents.
Programmable Logic Controller (PLC) (Types of PLCs (Compact., Modular.,…
Programmable Logic Controller (PLC)
Focuses on automating different electro-mechanical processes taking place in various industries.
The coding is programmed on a computer. From here it is transferred to the PLC using a cable.
It is programmed using a programming language called Ladder Logic. It is already known that PLC is an industrial computer.
A Programmable Logic Controller consists of various input and output terminals. Using the input terminals, PLC interprets the logical states from switches and sensors.
There are two logical states also known as high(or 1) and low(or 0).
Process of a scan cycle consist in:
Reading inputs
Executing the program
Processing communication requests
Executing CPU diagnostics
Writing outputs
Main components of a PLC.
Processor:
Rack/Mounting:
Input Assembly:
Output Assembly:
Power Supply:
Programming Device/Unit:
PLC programming is used for:
They are used in industries that utilize control-systems since they can operate on their own once programmed
They are used to build systems in some industries
You can also find them being used in your washing machines and also for traffic lights
Parts of PLC
The power supply.
Central Processing Unit (C.P.U))
Input and output module.
Exit module.
Memory module.
Programming terminal.
Peripheral.
History of PLCS
The first Programmable Logic Controllers were designed and developed by Modicon as a relay re-placer for GM and Landis.
These controllers eliminated the need for rewiring and adding additional hardware for each new configuration of logic.
The new system drastically increased the functionality of the controls while reducing the cabinet space that housed the logic.
The first PLC, model 084, was invented by Dick Morley in 1969
The first commercial successful PLC, the 184, was introduced in 1973 and was designed by Michael Green
Types of PLCs
Compact.
Modular.
Rack mount.
With operator panel.
Industrial Computer.
Slot.
Software Type.
Low Band.
