If the Brsh of DC motor is shifted by 90 deg, then MNA will
shift by --degree.

Answer Posted / rakesh kumar

mna refers to the axis along which the resultant flux is
0 , which coincides with the geometric neutral axis when no
armature current flows but the flow of armaue current
shifts the 0 flux position or the mna in the direction of
rotation in a generator and opposite to it in a motor ,
ideally the brushes should be along the mna as then it
would be unde the influence of no rotational emf induced
due to earlier pole once the the coil crosses the brush or
undergoes commutation , the shift of brushes has got
nothing to do with the shift of mna that is the mna should
remain at the same position , however for the sparkless
commutation mna shoild be along the brush and hence it
would be good if the mna also gets shifted by 90 .

Is This Answer Correct ?    7 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

do we use neutral grounding for resistive balanced load? if we use what happen?

1326


Which Class insulation is prefered for the sandwich Busducts ? Why?

1539


how can we calculate the ratio of caustic soda and water in lrs.

5166


what is the affect of earth's magnetic field on the frequency used in aircraft???

1533


How CFL &T5 tube light glows?

1590






how to calculate the earth mat design in 132 kv substation yard ????

5715


What is essential to prove safe isolation of electrical circuit?

624


How to size Air Circuit breaker (ACB)? What is the most important factors?

1778


What is CVT and what is relation with wave trap?

1653


This is urgent!! What is a Thyristor-based 3-ways selector switch with Zero crossing control? how does it operate and where is it mostly found in a system?

1570


What are reasond for high wattage in single phase induction motors

1363


relation between power station capacity and voltage level?

1580


how we can calculate power factor in single phase & three phase ?thank u

1554


Comment on the working principle of operation of a single-phase transformer.

693


What is the previous name of Cox's Bazar

1688