Everything about PLC-5

The PLC stands for Programmable Logic Controller. A PLC is an innovatively designed computer that helps to perform specific functions in an easy way also in harsh environments that includes excessive dry, wet, or rainy circumstances. PLC can be used to automate industrial processes including manufacturing plant assembly, processing of plats, or even wastewater treatment plan. 

Several features of the personal computer you own at your home can be used by PLCs. The Central Processing Unit (CPU), inputs and outputs (I/O), memory, and operating software can have both power supplies. 

The main difference between PLC and PC is that PLC can perform discrete and continuous functions that PC fails to do. A PLC can be recognized as the ‘ruggedized’ digital computer because it looks after the electromechanical working process of an industrial environment.

PLC block diagram

Are you searching for the PLC-5? Well in this article you will know everything about the PLC-5. So, without wasting any further time let’s know about this. 

How does a PLC work?

To under5stand the working of the PLC-5, you need to understand the cyclic scanning method of PLC commonly known as the Scan Cycle. 

Organizational Block

Start Cycling Time Monitoring

Read Data from Input Module

User Program Working

Write data into output module

Other Tasks

A block diagram representing the PLC-5 working

Furthermore, some steps have been mentioned so that you can clearly understand the working of PLC-5

  1. The monitoring of and THE cycling procedure gets started by the Operating System.

  2. The CPU engages in reading the data from the input module and also checks the status of all the inputs. 

  3. The execution of the user or the application program written in relay-ladder logic is done by the CPU as well and also reads any other PLC programming language. 

  4. After this, the CPU starts the internal diagnosis and communication task. 

  5. According to the program results, the CPU writes the data into the output module. This is done to get all outputs updated. 

  6. The overall process performs continuously until the PLC-5 is on a run mode. 

What are the Types of PLC?

PLC-5 can be divided into 2 types. The two types of PLC are fixed/compact PLC and Modular PLC. Let’s discuss it in a vast way:

  1. Compact PLC

Compact PLC-5 has a fixed number of I/O modules and external I/O cards. It does not further have the capacity to expand the modules and all the inputs and outs of Compact PLC shall be decided by the manufacturer. 

  1. Modular PLC

Modular PLC provides permits to multiple expansions with the help of ‘modules’. And that is the reason it is known as Modular PLC. I/O components can increase in this as the component is independent on each other. 

PLC can be further divided into three types according to the output that includes Relay Output, Transistor output, and Triac Output PLC. The Relay Output is best for both AC and DC devices whereas the Transistor Output uses switch operators and is found inside microprocessors. 

Moreover, according to the size of the PLC, it is further divided into MINI, Micro, and Nano PLC as well. 

What is the Importance of PLC?

PLC-5 is highly important in the field of automation, and SCADA systems. According to the operational requirement process the PLC can further be programmed. 

The main advantage of PLC is that it can control the hard weird system. IN PLC you can go back and forth and can further change the program that you have set before at a little cost of time. In a PC or any other hard weirs system, you have to start from the beginning scratch. 


So, with the above points, you already know for what reason you should consider PLC. With this, you can make your life easier and can further functionalize a lot of things.

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