Gearbox Efficiency vs Input Speed

For most gearbox models, efficiency varies across rpm. However, most vendors state a single rated efficiency for all speeds. This is sufficient in most cases when the efficiency varies slightly across the entire speed range. However, some gearboxes see their efficiency vary significantly throughout the speed range. The efficiency vs input speed curve is used to calculate the proper efficiency at the specific speed. Hence, all performance calculations are more accurate, and require no estimation or adjustment by the user.