Electric Motor Speed Formula

Note that when an ac motor is loaded the spinning magnetic field in the stator does not change speed.

Electric motor speed formula. So for example if you have a 4 pole motor on 60 hz then rpm 60 2 4 60 1800 rpm. Where p out output power measured in watts w. The power supply frequency and. A four polethree phase induction motorwhen operated at 60 hz will be very close to 1800rpm synchronous speed the rated full load speed will be less than synchronous speed by the value of slip a four polethree phase induction motorwith a ratedfull loadspeed of 1750 has a slip rating of 2 7 by formula.

P out τ ω. Note an induction motor will never reach its. The rotor speed of a 4 pole induction motor at 50 hz is 1200 r min. Slip of a motor can be found from the formula.

It is motor speed and torque the turning force of the motor. 60hz is the most common frequency in the us. For example 2 or 4. P number of poles.

S η sync η m η sync 100. Poles number of poles of your motor. Motors supposed to do some work and two important values define how powerful the motor is. N shaft rotation speed rev min rpm.

η sync speed of magnetic field. N f 2 p 60 1. Rpm shaft rotation speed or revolutions per minute. Where η sync 120 50 4 1500 r min.

Normally at it s top at operating speed. The torque is the twisting force that makes the motor running and the torque is active from 0 to 100 operating speed. The motor speed in rpm is calculated as n s 2 cdot 60 cdot dfrac f p. The power produced by the motor depends on the speed of the motor and is.

P number of poles. F frequency of electrical power supply hz cycles sec 1 s. The synchronous speed can be calculated as. This can be found on the nameplate of the motor.

η m mechanical shaft speed. Hz frequency or cycles sec. Using this formula you can see that a four pole motor operating on the bench under no load conditions runs at 1 800 rpm 7 200 ã 4 poles. The full torque from zero speed is a major advantage for electric vehicles.

Rotor speed η m 1200 r min. 50hz is the most common frequency outside the us. Motors run at a specific revolutions per minute rpm and a speed reducer is needed if you want to keep that motor but have a lower rpm. Zero at 0 speed and.

For example 50 hz or 60 hz. The number of poles in the motor winding. Calculating the rpm resulting from a motor and speed reducer assembly requires only basic mathematical knowledge. The motor speed calculator calculates the synchronous motor speed from the following parameters.

F supply frequency hz. Dc controls adjust speed by varying the voltage sent to the motor this differs from ac motor controls which adjust the line frequency to the motor. Output mechanical power of the motor could be calculated by using the following formula. 50 x 60 x 2 6 000 no load rpm ã number of poles.