Position Feedback Sensor (Servo)

This position feedback sensor is a component designed for use in pneumatic and servo actuator systems. It continuously monitors the angular or linear position of the actuator shaft or piston and reports this information to the control system, enabling closed-loop control for accurate positioning. The sensor typically employs technologies such as potentiometers, optical or magnetic encoders, or resolvers to convert mechanical position into an electrical signal—analog voltage, digital pulses, or serial data—which is transmitted to the servo controller for verification and adjustment. The device is housed in an aluminum alloy enclosure with a stainless steel shaft, and the internal PCB carries the sensing elements. Key parameters include a supply voltage of 24 V DC ±10% with reverse polarity protection, a 4–20 mA two-wire loop-powered output signal, a measurement range of 0–100 mm (custom ranges available), a linearity error of ±0.05% FS, repeatability of ±0.01% FS, an operating temperature range of -40 to 85 °C, ingress protection rated IP67 per IEC 60529, housing material of 316L stainless steel per ASTM A240, and a weight ranging from 0.5 to 1.2 kg depending on the range. These specifications are directory reference values and must be verified with the legal manufacturer or supplier for the specific model and application. The sensor is suitable for harsh environments due to its corrosion-resistant housing and high ingress protection. It is essential to confirm that the sensor's electrical interface and mechanical mounting are compatible with the actuator system. Regular maintenance should include checking for signal drift, mechanical wear, and proper sealing. Failure to maintain the sensor may result in inaccurate position feedback, leading to positioning errors or system instability.

The sensor converts mechanical position into an electrical signal using one of several technologies. A potentiometer uses a wiper sliding along a resistive element, producing a voltage proportional to position. An optical encoder uses a patterned disc and light source to generate digital pulses, while a magnetic encoder uses a magnet and Hall sensors. A resolver uses transformer principles to produce analog signals. The resulting signal—analog voltage, digital pulses, or serial data—is sent to the servo controller, which compares it to the desired position and adjusts the actuator accordingly. This closed-loop feedback ensures accurate positioning.