Programmable Logic Controllers (PLC)
PLCs are tough and reliable digital computers used to control machines and factory processes. Since the 1960s, they’ve been commonly used in industries like car manufacturing, packaging, and material handling. PLCs were first created to replace old systems like relays and timers. Today, they can perform fast and complex tasks, making them ideal for automatic control in many types of machines.
Distributed Control Systems (DCS)
DCSs are control systems mainly used in industries such as chemical plants, oil refineries, and power stations. A DCS has several controllers placed in different parts of a plant, each one managing a specific section of the process. Unlike PLCs, which are used for machines that start and stop, DCSs are designed to control ongoing processes that need continuous monitoring and adjustment.
Which One to Choose?
If your system needs to control many process variables or needs backup systems for safety (high redundancy), a DCS is likely the better choice.
If you have a small or medium-sized system and need fast, reliable control, a PLC is usually more suitable.