An analog output module in PLC is a component that converts digital signals from the controller into continuous analog signals, such as 4–20mA or 0–10V. This allows the PLC to control field devices that require variable output instead of just ON/OFF signals. The conversion is done using a Digital-to-Analog Converter (DAC) built inside the module, ensuring smooth and accurate signal transmission.
In simple terms, an analog output module helps the PLC send variable commands like “increase motor speed slightly” or “open valve halfway.” This is essential for processes that need fine control over motion, flow, temperature, or pressure. Typical output standards include 0–10V and 4–20mA, depending on the field device. These modules are commonly used in automation systems for applications such as heating control, servo positioning, and flow regulation. For instance, the Mitsubishi FX5-4AD Analog Module offers high-precision control for analog devices in industrial PLC systems. In short, the analog output module bridges the gap between the digital logic of a PLC and the real-world analog signals required for continuous process control.