Definition of PLC

A programmable logic controller (PLC)or programmable controller is an industrial computer that has been rugged and adapted for the control of manufacturing processes, like assembly lines, or robotic devices, or any activity that needs high-reliability control and simple programming and process fault diagnosis. PLC programs are typically written during a special application on a personal computer, then downloaded by a direct- connection cable or over a network to the PLC. The program is stored within the PLC either in battery- backed-up RAM or another non-volatile non-volatile storage . Often, one PLC are often programmed to exchange thousands of relays. Volatile flash memory. Often, one PLC are often programmed to exchange thousands of relays. The functionality of the PLC has evolved over the years to include sequential relay control, motion control distributed control systems, and networking.