German manufacturer KTR has extended its product range for wind turbines with recent yaw brakes. The KTR-Stop Yaw brake makes sure that the nacelle is held in a required direction. It differs from a rotor brake in that the azimuth system is always active. When the nacelle turns, the Yaw brake is controlled so it produces 10 to 20 % of their retention force. In this way, azimuth (yaw) drives are protected against impacts and pulsating loads. Brakes used this way typically have clamping forces of about 500 KN or 50 tons. Large wind turbines can have azimuth brakes with up to 10 calipers positioned to accept high loads which correspond to twisting of the nacelle even during extreme wind loads.