What is the difference between an RTU and a PLC?

RTU (Remote Terminal Unit) is designed for remote data acquisition and control, often in harsh, outdoor environments. Key differences: RTUs have wide operating temperature range, low power consumption (solar capable), strong communication focus (radio, cellular), and simpler control logic. PLCs offer more powerful processing, complex control algorithms, and are designed for factory environments. Modern distinctions are blurring - PLCs with RTU features are common. RTUs are typical in oil/gas wellheads, water/wastewater stations, and electric substations.