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
A DOL starter connects the motor terminals directly to the
power supply. Hence, the motor is subjected to the full
voltage of the power supply. Consequently, high starting
current flows through the motor. This type of starting is
suitable for small motors below 5 hp (3.75 kW). Reduced-
voltage starters are employed with motors above 5 hp.
Although DOL motor starters are available for motors less
than 150 kW on 400 V and for motors less than 1 MW on 6.6
kV. Supply reliability and reserve power generation
dictates the use of reduced voltage or not

To reduce the starting current of an induction motor the
voltage across the motor need to be reduced. This can be
done by autotransformer starter, star-delta starter or
resistor starter. Now-a-days VVVF drive used extensively
for speed control serves this purpose also.

Is This Answer Correct ?    436 Yes 59 No


 
  prakash
 
View All Answers
 
 
Please Help Members By Posting Answers For Below Questions
 
 Question Views   Select
 
how to identify conection leads of an unknown electric motor 269
Formulae for calculating the transmission line losses for different voltage levels 406
CAN WE CALCULATE THE NEGATIVE SEQUENCE AND ZERO SEQUENCE REACTANCE OF A GENERATOR USING ONLY ITS RATED VOLTAGE, KW, PF AND SYNCHRONOUS REACTANCE??? IF YES, THEN HOW?? 2642
sir i had plane to do some project with the base of hopkinson test in AC supply its possible 195
how we can calculate chiller required ampear? 374
what is stper motor 547
Show Details FROM:Muhammed Ikram TO:qa@allinterview.com Message flagged Saturday, June 4, 2011 10:07 PMMessage bodyHello all, i want to ask a question to all of you that what is VMM (voltage monitoring module )? how it work,s? i heard somewhere that it compare 1 phase voltage to other phase voltage. but there is also some setting on it. how to set it,s setting. please tell me briefly. Thank,s and Regard,s. Muhammed Ikram. 237
What is the difference between diode and a transistor in terms of the direction of current flow? 544
Refernce currents are to be generated using refernce cueernts how can this be done 451
what is differnce btwen lll and lllg faults 249
What are the specifications for getting approval of Substation? 226
which protection used in power plant? 311
How to decide and select the different earthing wire size for the different types of earthing 523
PLease anyone can tell me CTUM-15 specification? 1894
what are the stresses in circuit breakers ? 225
E-Mail New Answers        Answer Selected Questions