The device or set of devices through which data is brought into another device. A device that reads input quantities (i.e., thermocouple, level switch). Devices such as limit switches, pressure switches, push buttons, etc., that supply data to a PES. These discrete inputs have a common return or an individual return (referred to as isolated inputs). Other inputs (may) include analog devices and digital encoders. Pneumatic, hydraulic, or electronic switches for common input devices such as pressure switches, flow switches, level switches, temperature switches, selector switches, and push buttons. Also see "sensor".
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