The static torque sensor is not much different from the dynamic torque sensor, the key is the sampling speed of the secondary instrument.
Dynamic torque sensors are typically used to test for sudden changes in torque. Torque or torque peaks such as tighteners, electric wrenches, motor output torque, engine output torque, and drill rod torque are required. Static torque sensors are typically used to test where the torque is slowly changing. The sampling speed is typically less than 50 times per second, such as testing a manual torque wrench, the transmission's static load torque, and so on.
In some cases, because the object being tested is rotating, the dynamic torque sensor can also rotate for testing purposes.