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RICH DAD POOR DAD BOOK REVIEW

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  RICH  DAD  POOR  DAD  BOOK REVIEW This is amazing book.   • Explodes the myth that you need to earn a high income to become rich • Challenges the belief that your house is an asset • Shows parents why they can't rely on the school system to teach their kids about money • Defines once and for all an asset and a liability • Teaches you what to teach your kids about money for their future financial success It's been nearly 25 years since Robert Kiyosaki’s  Rich Dad Poor Dad  first made waves in the Personal Finance arena. It has since become the #1 Personal Finance book of all time... translated into dozens of languages and sold around the world. Rich Dad Poor Dad  is Robert's story of growing up with two dads — his real father and the father of his best friend, his rich dad — and the ways in which both men shaped his thoughts about money and investing. The book explodes the myth that you need to earn a high income to be rich and explains the difference between working
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Armature winding in detail

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Armature Winding

  • Armature winding is always closed and double layer type closed means all winding are connected in series to form a closed circuit. the junctions of two coils terminated on copper segment called as commutator segments.
  • A coil has two sides occupying distinct specified slots. To maximum induced emf, the spacing between two ends should be kept at 180° electrical. it means if one side is under North Pole then other should be under South Pole.
Coil span
spacing between the two sides of coil. The spacing is expressed in terms of number of slots between the sides.
if S is the total number of slots and P is the total no. of poles then coil span is S/P
E.g.: For 20 slots, 4 poles, coil span=5, if one side of a coil is placed in slots 3, then other end must occupy slot (3+5=8).

  • A double layer winding means that each slot has two coil sides (belonging to 2 different coils). one coil is placed in lower portion of slot and other above it.
  • if S=20, P=4, coil span=5, if a coil is housed in upper deck of slot 6, then other end should lie in lower deck of slot 11. Name of coil is (6-11).
Commutator pitch
The separation of coil sides in terms of number of commutator segments is called as commutator pitch (Yc).

Procedure to create Armature winding:-
  1. Type of winding (lap or wave), total number of slots S and total number of poles P will be given.
  2. Calculate coil span (≈S/P)
  3. Calculate commutator pitch Yc
        For lap winding, Yc = ± 1 and for wave winding, Yc = 2(S+1)/P
  
    4. We have to complete the winding showing the positions of coil sides in  slots, inter connection of the coils through commutator segments using appropriate numbering of slots, coil sides and commutator segments.
    5. Finally to decide and place the stationery brushes on correct commutator segments.


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