:: 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 In Companies :: ACC, Dalkia, Indeco, Wipro, Novotel, Engineering, NINL, RMH Control Systems,     < I also faced this Question! >
 Question Submitted By :: ravi
  Answer Posted By  
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 ?    457 Yes 61 No

View All Answers
Please Help Members By Posting Answers For Below Questions
 Question Views   Select
Explain M Var? Which types of problem occurs when reactive power increase at the time of full load of plant and at the time of synchronize of plant? 305
Please brief what is sinewave 384
how to calculate power consumption in slip ring motor at different step 446
how electricity is generated an supplied till consumer 331
hello!my name is sheikh iam preparing for indian engineering servieces,please send me the old question 327
why are the maintaine power factor and how can this control and this is how work. 290
what is transient stability analysis means? 353
draw vector diagram and +ve,zero sequence diagram of symmetrical three phase fault. 239
I have 200 KVA Isolation Transformer for UPS input side. & ups was having 48% load, suddenly got short what will be the reason. 573
What will be the sampling frequency that reveals the same sampled signal? 71
exolain the star delta connection 568
I need to connect a synchronous generator to the grid using automatic synchronization and two circuit breakers (one for synchronization, one for end connection to the grid), how to determinate the required diameter of the cables? 695
How can determine cable size with respect to cable length and area in mm2 291
what is the power rating of CPU, CRT type moniter, LCD type moniter,scanner Approx. 509
What are the types of excitation system? 278
E-Mail New Answers        Answer Selected Questions