How a PLC Programming works


A Programmable Logic Controller or a PLC is a computer or machine that comes with an operating system that is highly specific in managing processes in real-time. The PLC plays a very important role in the industry, especially in the processing, producing and manufacturing of different goods. So, if you are in a company with high tech facilities, then you might be working with engineers, who operates the PLC for monitoring and maintenance.

Not everybody understands how a PLC work. You have to be an expert in using the software for this type of environment as well as having a mastery of the language used in manipulating the system. For example, you must have a special training for RSLogix 5000, if this is the platform that the company you are working on is using. Without enough knowledge and skills of a PLC, then you would find it difficult to understand the operation of the system.

Even an engineer, who did not attend a specific training about PLCs won’t have sufficient skill to work for a PLC. That is why, if you have attended a training, then that would be your advantage to work as a PLC expert or operator. You will always have a lead over the other engineers because the PLC has a complicated process and learning it in a short time won’t be enough. Remember that this machine accepts various digital as well as analog inputs, executes a program and writes output.


The PLC Operation

Most PLC’s make use of a scan-cycle formatting, where it starts scanning the program from the top going to the bottom and then, from left going to the right. Every input that was scanned from the input card will be stored in the memory table.

After scanning the input, it will be logically executed using a program. And then, the input will also undergo a certain diagnosis, where it will be decided to perform a task and communicates this process or simply not to do anything.

When the process is completely diagnosed and executed, it will provide an output coming from the output memory table and it will be written through the output modules. Anyway, I have here a related site for you to check.


The PLC System


One of the components of a PLC is the rack, which holds every tangible part of the PLC. It may vary in size and shape, depending on the module that a company needs. This rack has a backplane, allowing communication between the cards and the Central Processing Unit or the CPU. The power supply is also needed to run the system. Most PLC’s works with a 120 VAC or a 24 VDC power source.

Another component is the CPU, which is actually the brain of the module and this one also varies, depending on how complex the system is. The CPU contains important parts, such as the memory chip, microprocessor and different circuits for monitoring, communicating and controlling logic. It …