What is a reasonable torque range for a motor, clutch, or brake?
Torque range starts with the maximum torque capacity of the motor, clutch, or brake. The other end of the range is harder to define, but is the minimum controllable torque with an acceptable variation from the set point. For example, a brake is capable of 200 N-m at maximum and the variation in performance is +/- 0.5% of maximum of this maximum. What would be the acceptable low-end controllable torque? This variation equals +/- 1 N-m. THe low-end acceptable torque depends on the acceptable variations at the low-end set point. If the goal is less than +/-10%, what torque is 1 N-m equal to 10%. The answer is 1 N-m / 0.1 = 10 N-m. In this case, the torque range is 10-200 N-m or 20:1.
