What Feedback Sensor Options Does PA Offer for Linear Actuators?
Position feedback turns a simple push-pull actuator into a precision motion control device. PA offers three main feedback technologies — potentiometers, Hall effect sensors, and internal limit switches — each suited to different accuracy and application requirements.
Feedback Technology Comparison
| Technology | Signal Type | Accuracy | Best For | PA Example |
|---|---|---|---|---|
| Potentiometer | Analog voltage (0–5 V) | ±1–3 mm (after calibration) | Arduino/microcontroller positioning, moderate precision | PA-14P |
| Hall Effect (incremental) | Digital pulses | ±0.5–1 mm typical | FLTCON sync systems, high-precision closed-loop control | PA-04-HS |
| Internal Limit Switches | Open/close circuit | End-of-stroke only | Simple stop-at-end applications, no mid-stroke positioning needed | Most PA standard models |
Potentiometer Feedback
A potentiometer is a variable resistor built into the actuator body. As the rod extends, the wiper moves along a resistive track, poducing a voltage proportional to position. PA's potentiometer actuators add three wires to the standard two-wire motor connection: a 5 V supply, a signal output, and ground.
- Pros:Simple analog interface, works with any microcontroller that has an ADC (analog-to-digital converter), absolute position (knows position even after power loss)
- Cons:Requires calibration per unit; signal accuracy limited by ADC resolution and electrical noise; potentiometer has a finite mechanical lifespan (~100,000 cycles)
- PA models:PA-14P— the primary off-the-shelf potentiometer actuator. Custom potentiometer variants available on other series on request.
Hall Effect Feedback
Hall effect sensors detect the passage of a magnet on the actuator's rotating lead screw, generating digital pulses that are counted by a controller to track position. PA's Hall effect system is used natively by the FLTCON control box series for synchronised multi-actuator control.
- Pros:Higher accuracy than potentiometer, longer mechanical lifespan (no contact wear), digital signal is less susceptible to noise
- Cons:Incremental (must re-home after power loss); requires compatible controller (FLTCON series or custom microcontroller code)
- PA models:PA-04-HS— the only off-the-shelf 24 V Hall effect actuator. Custom Hall effect options available for PA-03 and PA-18.
Internal Limit Switches
Most standard PA actuators include internal limit switches that cut motor power when the rod reaches full extension or full retraction. These provide no mid-stroke position data — they simply protect the actuator from stalling at end of travel.
💡 Which feedback type do I need? If you only need to move to full-in or full-out — use standard limit switch actuators. If you need to stop at a specific mid-stroke position — use potentiometer (simpler) or Hall effect (more precise). For synchronised multi-actuator systems — use Hall effect with FLTCON controllers.