why field resistance is higher than armature resistance in
dc machines? and why filed resistance is kept at min value
at starting in same time of armature resistance at max value?

Answers were Sorted based on User's Feedback



why field resistance is higher than armature resistance in dc machines? and why filed resistance is..

Answer / sai

To allow the maximum current through the armature, resistance is kept to very low value. According to ohm's law, V=IR.
As R is very low then current becomes maximum.

Is This Answer Correct ?    21 Yes 10 No

why field resistance is higher than armature resistance in dc machines? and why filed resistance is..

Answer / lokesh luckky

It has two reasons
1) in DC generator to allow large generated currents to output.
2)in motor (torque is proportional to current) so to produce high torque we must allow high currents through winding.

Is This Answer Correct ?    7 Yes 0 No

why field resistance is higher than armature resistance in dc machines? and why filed resistance is..

Answer / abdelbaset

because the consumable power in the field circuit assuming
the same voltage of the main circuit is lower than the
armature circuit. so the excitation current is lower than
armature current so field resistance is greater than
armature resistance

Is This Answer Correct ?    11 Yes 16 No

why field resistance is higher than armature resistance in dc machines? and why filed resistance is..

Answer / binod

field resistance always more than the armature resistance
of a d.c machine(shunt or series or compound).magnetic flux
created by field.to vary generate e.m.f the field
resistance vary from min to max with increase/decrease of
speed.in motor case the speed can be vary by varrying the
field resistance(addition or substraction) with the
required torque.

Is This Answer Correct ?    6 Yes 19 No

Post New Answer

More Electrical Engineering Interview Questions

which theorem is used to analyse fault a)thevinin b)Norton c)Superposition d)jordan

1 Answers   FFC, NTS,


definition of transformer

10 Answers  


how many earthings will be required for 1 isolator & 2 VCB, which are connected to a 1600 KVA Distribution TRansformer?

2 Answers  


what is the meaning of electrical maintenance?

3 Answers   GE Healthcare, MAHINDRA,


In Aeroplane what circuitry or method use for earthing?

9 Answers   Bhel, EDA, Wind World,






what is the minimum insulation resistance for HT AND LT motor ?

3 Answers  


what is the difference between "ampere trip and ampere frame"

1 Answers  


I have 380.KVA DG set how to Calculate the units from DG.

2 Answers   Ozone Pharma, Sperry Plast Limited, Sterling,


prefer any good electrical engineering book.....it should be useful in the practical fied?

1 Answers  


What will be result if we connect LT votage to the terminal of HT Transformer?

3 Answers   Equate,


what is a difference b/w earthing & neutral?

5 Answers   ABB, KEC, Sterlite,


what is tpdt

4 Answers  


Categories
  • Civil Engineering Interview Questions Civil Engineering (5085)
  • Mechanical Engineering Interview Questions Mechanical Engineering (4451)
  • Electrical Engineering Interview Questions Electrical Engineering (16632)
  • Electronics Communications Interview Questions Electronics Communications (3918)
  • Chemical Engineering Interview Questions Chemical Engineering (1095)
  • Aeronautical Engineering Interview Questions Aeronautical Engineering (239)
  • Bio Engineering Interview Questions Bio Engineering (96)
  • Metallurgy Interview Questions Metallurgy (361)
  • Industrial Engineering Interview Questions Industrial Engineering (259)
  • Instrumentation Interview Questions Instrumentation (3014)
  • Automobile Engineering Interview Questions Automobile Engineering (332)
  • Mechatronics Engineering Interview Questions Mechatronics Engineering (97)
  • Marine Engineering Interview Questions Marine Engineering (124)
  • Power Plant Engineering Interview Questions Power Plant Engineering (172)
  • Textile Engineering Interview Questions Textile Engineering (575)
  • Production Engineering Interview Questions Production Engineering (25)
  • Satellite Systems Engineering Interview Questions Satellite Systems Engineering (106)
  • Engineering AllOther Interview Questions Engineering AllOther (1379)