An encoder in an elevator system is an electromechanical sensor attached to the traction machine or motor shaft that measures the rotational speed, direction, and position of the drive. The controller uses encoder signals for precise speed regulation, accurate floor levelling, and safe stopping. High-resolution encoders (typically 1024 or 2048 pulses per revolution) enable smooth acceleration and deceleration profiles and millimetre-accurate floor levelling, which is critical for accessibility compliance.