Electric Motor Torque Ratings

Accelerating torque available motor torque load torque.

Electric motor torque ratings.

T inlb p hp 63025 n 1. Reduced voltage soft starters. Fla according to the voltage rating. Gas engines are usually rated for horsepower and torque at a specific rpm go under or especially over and the torque drops off.

Horse power and speed in rpm. T inlb torque in lb f. Electrical motor power velocity and torque equations. P hp horsepower delivered by the electric motor hp.

Torque in imperial units can be calculated as. 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. For an electric motor torque increases a gasoline motor has a peak torque value for a given rpm 3600. The actual speed of the turning rotor will slow down below the nameplate rated.

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. These equations are for estimation only friction windage and other factors are not taken into consideration. 1 ft lb f 1 356 nm. 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.

It s easy to peg that as a hp rating measured torque at a fixed rpm. 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. P t v 5 250. T ftlb torque lb f ft.

The following calculators compute the various torque aspects of motors. Electric motors can be powered by direct current dc sources such as from batteries motor vehicles. You load it the rpm drops and it draws more current and produces more torque. Electric motors have a rated horsepower hp.

N revolution per minute rpm alternatively. Motor power then is the torque times the angular speed.