why the AC or DC motor takes high starting current?
Answer Posted / harshid agrawal
because at the starts dc motor do not have the back emf and due to that applied voltage is not oppose by back emf and winding have small amount of resistance so according to ohm's law current increse to 50-60% of it's rated current.
and in case of ac motor as the at the start there is no any rotation of the rotor wrt stator winding and the emf induced in the rotor winding depens upon the flux link with it and it's relative speed as the we apply full rated voltage at first it cause max flux link with rotor as it remain stationary and max emf induce in rotor winding as rotor winding is short circuited in induction motor it cause high flow of current in rotor .
that's bot ac and dc takes high current @ starts
| Is This Answer Correct ? | 6 Yes | 2 No |
Post New Answer View All Answers
how to Select Lighting arrester? What r the parameters to be considered for the selection of Lighting arrester ?
How to back charge the Gas turbine generator
How do u analyse protection fault when vcb tripping on load
anyone please send transformer parameter design formulas & details of tap changer ? plz i have interview this week its more helpful for me ?
How to know the Max. current caring capacity of the cable by its size ?
What do you mean by cogeneration? What its working principle?
100 MVA 3-phase alternator with earthed neutral has a reactance of 5 ohms per phase. what will be the fault MVA of generator.
What is transformation ratio what it describes?
State the types of distortions in amplifier?
Why need 3phase machine double earthing?
what material is used in capaciter
What is the drawback of static coefficients?
A 3-phase IM is supplied from 50 Hz system. It runs at speed of 1440 rpm and slip equal to 4 %. Calculate number of pole pairs. A 1 B 6 C 2 D 3
can anyone explain the star-delta motor control wiring ,which wire go where and how they operate?
In a tap changing transformer where is the tap connected, is it connected in the primary side or secondary side?