Balluff's magnetic encoder systems can report the speed of wind turbine rotors with extreme accuracy, even at low speeds. The magnetic tape measurement system is simply wrapped around and attached to the main shaft. The system communicates standard quadrature incremental encoder signals that are compatible with many control systems. The encoder system can determine the direction of rotation and can also provide position feedback to determine the correct position to engage the rotor lock for service.
The encoder system operates without mechanical contact between the reader head and coded track. The generous reading distance of the system tolerates real-world variability in concentricity about the rotational axis, increasing installation flexibility and reducing costs.