PLC vs. Microcontroller



PLC vs. Microcontroller: PLC and Microcontroller both are used in automation industry. But there is a major difference between area of their applications. So to know that first of all we have to understand the difference between the two.
As we know Microcontroller is a chip (IC), could be 20 pin, 40 pin or else. Pins of a uC are very sensitive and requires high care while handling. These pins can easily break. On the other hand manufacturers of PLC make the outer body of PLC with very robust material. It can withstand jerks, temperature hikes etc.
uC is a device that mostly works on 5VDC. Whereas PLC can work on different voltage ranges like 12VDC, 24VDC, 48VDC, 110-240VAC etc.
uC has a limited number of Input/Outputs and it can’t be extended with extensions. Whereas PLC has a wide range of I/Os available and further it can be extended with compatible extension modules.
uC requires additional circuitry to transfer any programs in to it but PLC requires just a programming cable to burn any programs into it.
So……
A microcontroller contains one or more CPU’s along with memory and programmable input or output peripherals. Program memory in the form of Ferroelectric RAM, NOR flash or ROM is also often included on chip, as well as a small amount of RAM.
A programmable logic controller called shortly PLC, or programmable controller is an industrial digital computer which has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, or robotic devices, or any activity that requires high reliability control and ease of programming and process fault diagnosis. 

From above differences we conclude that PLC is a device that we can use in industrial automation for controlling various machines and other industrial processes. Its robust outer body makes the use of PLC in extreme industrial environments. We can connect a large number on input/outputs so makes it possible to control whole manufacturing plant on a single device.
Microcontroller can be used in car automation, home automation etc. where the requirement of I/Os if not much and the whole system is running at a low voltage.

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