plc

programmable logic controller, purpose-built embedded computer systems used to monitor and control industrial equipment. The bulk of them today are about as powerful as a 286 PC or even less and they cost as much as or more than a high-end PC. Despite that, the hardware and firmware/software in a PLC is designed from the ground up for deterministic, hard-real-time operation and I/O intensive applications. They also do not have processor fans, hard drives and other unreliable mechanical parts.