Interested to Buy Any Domain ? << Click Here >> for more details...
Answer Posted / shyam prakash ray
The principal is to keep the starting current in safe limit
so that the motor achieves 70% of speed as connected to
star side, since the motor draws very high current at the
time of starting due to high starting torque.
Once the motor gets started then it is changed/converted
into delta side either manually or automatically for
running.
| Is This Answer Correct ? | 32 Yes | 7 No |
Post New Answer View All Answers
how to calculate voltage drop and followed by cable calculation?is there avail in formula?
there is an alternator 480 k.w, 400v,50hz, 4-wire running on load having leakage alternator body earthed current 38 A. is it within acceptable limit? if yes then give reference if no then how to bring within specified limit
what is the relative size of single and three phase?
I Just want do EHS Certified Certification Distance Course From Govt approved,so can any body provide me details.
How many turns are there in primary winding? (In Transformer)
7- What is the Dissipation Factor and the difference between it and Insulation Resistance Test? 8- What is the task (function) of DC and AC reactors in power plant? 9- What is the task (function) of (open delta with earthed) in some types in transformers? 10- What is the base of the selection of the vector group in transformers? 11- What is the zig-zag transformer and its function by drawing in large detail? 12- What is the polarity ? 13- Why we make short between phase(R) in high side and phase (r) in low side in vector group test? Where High Side ( R ,S and T ) and Low Side ( r ,s and t ). 14- What are the time on delay and time off delay? 15- What is the vector group? 15- What is the task (function) of different types of vector group such as Dyn11 , Dd0 , YNd1,……..,?
Thumb rule of cable size(rm>30 rm)X multiplying factor=ampere
Is it possible to measure correct value of earth resistance & cable insulation ristance with out disconncting earth lead & both sides of cable ends? If not, any other method to measure ER & CIR with out disconneting from the system.
explain working principle of earth leakage relay
how to calulate short circuit current for the following: 1.cable connecting 11KV of 22KV/11KV transformer to 11Kv of 11KV/415V transformer 2.what cable size should i use.
What is slip in an induction motor?
What is inrush current? how can calculateit? what is the affect of it?
Dear Mr B C pal...Can you plz. put some light on principle of operation of Z-Ct in conjunction to its use with 1Cx1000Sqmm HT Cables & Directional Ground Fault / Over Voltage Relays...Regd..Parag v K 9899115632
Dear friends, i would like to know that what is the exact function of 'exciter winding' & 'aux winding' in Alternator?
Mention the methods for starting an induction motor?
