ALLInterview.com :: Home Page
 Advertise your Business Here     
Browse  |   Placement Papers  |   Company  |   Code Snippets  |   Certifications  |   Visa Questions
Post Question  |   Post Answer  |   My Panel  |   Search  |   Articles  |   Topics  |   Errors
   Testimonials Refer this Site  Refer This Site to Your Friends  Site Map  Contact Us      
   
 
Categories >> Engineering >> Electrical Engineering
 
 


 

 
Question What is the d/f between DOL & star delta starter & automatic
star delta starter?
 Question Asked At :: indeco, what is the rating of fuse in building?, wipro, ninl, engineering ac machines assigment, dalkia, novotel, rajendra mallick, star delta starter used for?, rmh control systems, acc cement
 Question Submitted By :: ravi
I also faced this Question!!    
Answer Posted By  
 
Answer
in induction motor the torque is propotional to squre of
supply voltage in case of dol the motor directly connected
to supply so torque is more while in star delta the motor
is firstly connected to star hence voltage is reduced
torque will be less and when motor reaches its 80% of speed
it connects with delta with the help of timer then full
voltage is supplied hence less rating motor should be
started with dol but for high rating it should be with star
delta

Is This Answer Correct ?    47 Yes 7 No


 
  honey
 
View All Answers
 
 
Please Help Members By Posting Answers For Below Questions
 
 Question Views   Select
 
Bimetal strip used in overload relay what is that,which types of material used for that & percentage. 403
Is it true that in the 3 phase transformer, the limbs of the core are at 45 dgrees to each other. if true, why? 331
what is the circutor?why we use it ? 578
how to calculate magnetic force genrated by a coil ? 361
what is the function of bearing in dc mchine" and where it is placed 870
Q.1:What protection will be used on HT and LT side of 33/0.4 KV, MVA transformer. Indicate capacities of protective device to be used. Q.2:Which types of back-up protections are used in the power transformers? What do you understand by the term over travel in the relay? Q.3:How star and delta connected winding transformer are provided from earth fault 314
How to do cable earhing? whether by grounding Armour to ground or by running extra G.I wire along with cable? which one is preferred mostly amoung them? If the second one is more preferable how many GI wires to be run along with cable (1 or 2)? 273
How to design the earth grid for lightning protection in an industry 1402
Difference between HRG and NGR. Are they both the same thing 900
What is online and offline ups? how does it works? 278
In HVDC LINE RECTIFIER CONTROL ON CONSTANT CURRENT AND INVERTER CONTROL CONSTANT EXITATION ANGLE CONTROL BUT HOW INVERTER CONTROL CONSTANT CURRENT? 214
dear all, How do i increase UPS (1000VA)backup time ? i have connected 2 12v wold you please 120 aH battery externally. ups charge the lead acid battery only 12.7 volt. backup time only 10.00 minuts and gose off. can any one of you help me? 419
limitation of conductor height on ground when we consider EMC 220
how much allowable resistance that can be difference in motor all coils? 520
what is mean by dual digital protection in the relay field? 245
E-Mail New Answers        Answer Selected Questions