Mell Why the no load current of an induction motor is so high as compared to a transformer of identical rating?
Magnetic circuit of Induction motor has large reluctance than transformer due to air gap between stator and rotor, more mmf(magneto motive force is equal to product of current and number of turns) or more current is required to set up working flux in Induction motor, this is the reason of high no load current in …
How long is inrush current?
These currents can be as high as 20 times the steady state currents. Even though it only lasts for about 10ms it takes between 30 and 40 cycles for the current to stabilize to the normal operating value.
Why is the starting current of induction motor high?
Starting Current in Induction Motor: Starting current of induction motor is as high as 5 to 7 times the normal full load current. Therefore different starting of induction motor, methods such as (star delta starter, auto transformer starter and other starting methods) are employed in order to reduce the high starting currents of induction motor.
What’s the difference between a starting current and a running current?
After some brief amount of time, it usually comes to the normal operating current which is a normal current which is mentioned on the Nameplate of the motor or on the manual. Running Current or Operating current is the same thing. Starting Current is the current required to rotate the rotor every time the motor is run from a stop condition.
Why does an AC motor draw excessive current?
When an AC motor is first energized, excessive current is drawn on the circuit supplying the motor, well beyond the current levels specified on the motor nameplate. High resistance is often encountered when starting a motor from a static (idle) position, and excessive current draw is necessary to begin rotation of the motor shaft.
What’s the difference between full load current and rated current?
In simpler terms. Full load current: Is the maximum current that a electrical machine can draw/supply safely by meeting (either supplying or consuming) the full-load conditions. Rated Current: The current rated on the nameplate of a electrical machine (this is in-fact full load current).