An induction motor has a lagging power factor. Motors of more than about 2 HP are designed to have a power factor of 0.85 or higher.
When you do a load test on a 3-phase induction motor you are checking the power factor, viz slip, and efficiency of the motor. You can test various loads with this test.
Torque is the cross product of radius and force .Torque is a twisting effect. Torque is the cross product of radius and force .Torque is a twisting effect.
The pullout torque is the maximum torque a motor can achieve. Also known as breakdown or peak torque. It occurs at the point where, the increase in the rotor current is exactly balanced by the decrease in the rotor power factor.
In dc motors, the electric power is conducted directly to the armature (i.e., rotating part) through brushes & commutator. Hence, in this sense a dc motor can be called as a Conduction motor. However, in ac motors, the rotor does not receive any electric power by conduction but by induction in exactly the same way as the secondary of a two winding transformer receives its power from the primary. That is why such motors are called as Induction motors. An induction motor can be treated as a rotating transformer i.e., one in which primary winding is stationary but secondary is free to rotate.
To answer this question, i need the power factor of the motor.CommentYou don't need the power factor, as you already know its true power (watts), but you do need to know the efficiency of the motor to determine its input power. You also need to know the cost per kilowatt hour.But you can get a rough idea by multiplying the number of kilowatts, by the time in hours, by the cost per kilowatt hour. For a more accurate answer, you need to divide this by the efficiency of the motor.
Induction motor comprised inductor as the most part in it and an inductor has the characteristic to oppose the change of current, i.e., it has lagging power factor as current lags behind the voltage. Hence, an induction motor works on lagging power factor.
That indicates a fault in the induction motor.
Induction motor used in industries for variable speed machines . Induction motor has always lagging power factor. Less cost compared to syn. Motor.
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1. Induction Motor has an air-gap but transformer has no air gap rather it is mutually link. 2. Induction Motor has high no-load current than transformer. 3. Induction Motor is a dynamic device. 4. Induction Motor has high power factor.
I'm not sure I've ever seen an induction motor used to correct power factor; it is usually the induction motors that are causing the poor power factor. "Power factor correction" is usually accomplished by adding capacitors to the system to counteract the inductance of large motors.
When you do a load test on a 3-phase induction motor you are checking the power factor, viz slip, and efficiency of the motor. You can test various loads with this test.
slip power is a power which is develop by the induced voltage and current in an induction motor
There doesn't have to be but capacitors are sometimes used to correct the power factor.
Induction motors are designed for a certain power. If the power demand is lower than that, you still have to setup the magnetic fields as if you were going to supply that maximum power. As a result, the no-load power factor of an induction motor is quite small, i.e. poor.
If the power demand is lower than that, you still have to setup the magnetic fields as if you were going to supply that maximum power
It is maximum at about 75% to 100% of the motor rated load. Efficiency is maximum at unity power factor , when R=X and when variable losses Is equal to constant losses at rated load.