What is the term for a device that converts environmental signals into a format understandable by a process device?

The correct term for a device that converts environmental signals into a format understandable by a process device is a sensor. Sensors play a crucial role in various applications by detecting physical phenomena such as temperature, pressure, light, or motion and converting these into electrical signals or other forms that can be processed by devices such as controllers or computers.

Input devices refer to components that send data to a system for processing, but they are not specifically tuned to environmental signals as sensors are. Feedback involves the transmission of information regarding the output of a system back to the input to adjust and control the process. Although input can be a broader category that encompasses devices like sensors, the specific definition pertaining to converting environmental signals directly points to sensors as the most accurate answer.