why motor starting current is High ?

Answer Posted / rvg

Dear Mr. Gajanan, as you are dealing with more machineries,
i want to stress some points:
During starting of motor:

the armature(rotor) is stationary, and it does not having
any magnetic property to resist the applied rotational
frequency at that time.

so it will act as a conductor fixed at rotating magnetic
field and produce some eddy current loss, and with in short
period of time, it will develope some anti rotional effect
to resist the rotational field, ie: rotating with same
direction to reduce the eddy curent.Thats why after
starting current reduces.

inertia of the rotor also having some major role on the
starting current. The gap between rotor and stator having
role on the starting current and initial power factor.

Is This Answer Correct ?    22 Yes 11 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Single line diagram for dbb (double bus bar)system.

1468


what is the VA(Volt-amphere)? define with calculation?

775


Haw to check conductivity of budbar

1343


Best way to measure the Soil resistance of rocky soil, three probe method and four probe method

1455


Circuit diagram of tube light without starter using electrical choke

3646






what is the difference between dry and wet type of 132kV terminations. which one is durable

1550


Please help me regarding my one concern. - During earth pit testing we noticed that the Clean earth pit and dirty earth pit showing continuity (Resistance value - 5ohm) . I want to know that if both earth pit have separate location and there is not internal looping between PIT then why such continuity is showing on it . Because of this issue the field side all earthing point showing short. In PLC panel we are providing two types of earthing cable which is coming from separate earth pit (Clean and Dirty earth pit) because of earth PIT showing short our PLC is not complying spec . please help regarding this issues.

1099


What is a compensator?

659


WHY IL=IPH IN STAR AND WHY IPH=IL/1.732 IN DELTA? WHAT IS REASON BEHIND IT?

5589


how to determine Sq.mm size of finolex power cables.

1541


Why negative feedback is preferred in the control system?

858


why we use Test Terminal Block in 11 KV and 33 KV electrical panels.

956


I am having dual speed motor of cromton greaves make of 3.7 KW -1400 rpm and 5 KW - 900 rpm. Please let me know groups and winding connction for rewinding purpose.

1516


how many single tension hardware are required on a double circuit transmission tower?

1480


100 MVA 3-phase alternator with earthed neutral has a reactance of 5 ohms per phase. what will be the fault MVA of generator.

1845