First, we have to start by saying that PLC, or programmable logic controller, is a compact computer that features specific operating system. This particular operating system is highly optimized and specialized to handle most operations in real time.
You probably know that PLC has input lines, and sensors can connect with them to notify you on different issues such as when the temperature reaches a certain level. It also features actuators that connect to output lines with the main idea to signal or affect reactions to specific and incoming events such as an open valve, start an engine, etc.
You can check this by entering on Allen Bradley PLC training, and we decided to present you a slight introduction:
PLC Program Languages
You probably know that system is completely user programmable and it features language called Relay Ladder Logic or Relay Ladder. The name will present you the idea from the early days when PLCs came from relays.
The most common languages used for PLC programming are:
- Functional block diagram
- Sequential function chart
- Structured text
- Instruction list
- Continuous function chart
Brief History On PLCs:
Let us start from the beginning. PLC or programmable logic controller is a digital computer used in industrial processes to handle automation. You can use it to control machinery on assembly lines, light fixtures, and even amusement rides.
You can find it in many industries, which means that PLC comes with multiple arrangements of both analog and digital inputs and outputs as well as immunity to electrical noise, possibility to withstand harsh temperatures and resistance to impact and vibration due to the robust casing.
Software that controls machine operation features in non-volatile and battery-backed-up memory. It is a great way to produce real-time output results promptly.
Before PLC became popular, safety interlock logic, as well as sequencing and control in automotive industry, features cam timers, relays, dedicated closed-loop controllers and drum sequencers.
More information on PLC history, you can check by clicking here.
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