Understanding the difference between dynamic and static torque is vital in selecting the right torque sensor. Dynamic (rotary) torque measurement is required when the sensor must rotate with the shaft, typically when the component operates at high speeds and/or undergoes significant angular acceleration. The sensor measures the applied or transmitted torque through the rotating shaft. Static (reaction) torque measurement occurs when there is no or negligible angular acceleration of the rotating element, or more commonly, when the measurement is taken on the non-rotating reaction element of a system.