Electric Motor Torque Ratings

An electric motor is an electrical machine that converts electrical energy into mechanical energy most electric motors operate through the interaction between the motor s magnetic field and electric current in a wire winding to generate force in the form of torque applied on the motor s shaft.

Electric motor torque ratings.

Gas engines are usually rated for horsepower and torque at a specific rpm go under or especially over and the torque drops off. Electric motors can be powered by direct current dc sources such as from batteries motor vehicles. For an electric motor torque increases a gasoline motor has a peak torque value for a given rpm 3600. 1 ft lb f 1 356 nm.

Torque in imperial units can be calculated as. An electric motor produces torque in response to load. Fla according to the voltage rating. Electrical motor power velocity and torque equations.

T inlb p hp 63025 n 1. T ftlb torque lb f ft. Reduced voltage soft starters. If the torque requirements of the connected load increase beyond 1 horsepower and the motor is supplied either 208 volts 230 volts or 460 volts at 60 hz.

T inlb torque in lb f. Reduced voltage soft starters are used to limit the start current reducing the locked rotor torque or starting torque and are common in applications which is hard to start or must be handled with care like positive displacement pumps cranes elevators and similar. Horse power and speed in rpm. P t v 5 250.

Electric motors have a rated horsepower hp. You load it the rpm drops and it draws more current and produces more torque. Motor power then is the torque times the angular speed. A motor does an amount of work equal to the torque it delivers times the angle through which it turns.

The following calculators compute the various torque aspects of motors. These equations are for estimation only friction windage and other factors are not taken into consideration. T ftlb p hp 5252 n 1b. Electric motors start up with very high torque level off slightly under and maintain that level throughout if they are overloaded the torque drops quickly and the motor stalls.

It s easy to peg that as a hp rating measured torque at a fixed rpm. P hp horsepower delivered by the electric motor hp.