Explain What will happen when direction of field current is
changed (i.e, field excitation is reversed) in the
following machines?
1) Alternator
2) Synchronous Motor
3) D.C Generator ( Shunt or Seies )
4) D.C Motor ( Shunt or Seies )
- 3 Answers
- 16542 Views
- NTPC, Transco, I also Faced
- E-Mail Answers
Answer Posted / tpfasil200
Direction of rotation of dc motor can be reversed in 2 ways
1.reversing current through armature and interpole windings(if they exist)
2.reversing current through field windings,ie,through shunt and/or series winding..but not through interpole windings(if they exist)
Reversing current through the armature is preferred because reversing current through the field windings involves breaking and making highly inductive currents of the field windings.Also field reversal of compound motors requires connections of both shunt and series windings to be changed..
| Is This Answer Correct ? | 18 Yes | 1 No |
Post New Answer View All Answers
how we can explain arc heatng?
What is DC series motor?
why the earth is taken minimum in supplying? wather it the proportional factor to getting work any equipment or a power plant?
explain with diagram how to protect transformers and substations from over current with help of CT's?
why we use sinosidal voltage / current instead of others in system?
what are the main applications of transistor in non-linear region?
Explain the function and difference of Restricted earth fault, simple earth fault and sensitive earth fault with connection diagram.
how is calculated the quantity of weight in hot test xlpe?
We have two APFC panels in same station. I need how to connect CT in two APFC panels.can we take one CT in series connection or two separate CTs.
how we can adjust for three phase motor cold stall time ,hot stall time and thermal register set up?
what is dry and wet frequency withstand voltage? why & where it is used??
I am getting above 60 V as open delta voltage against single phase unit ICT at tertiary delta formed and ICT getting trippped on NDR. ICT tested and found in order. PTs provided on tertiary are tested and in order. what may be the reason?
WHY SEPARATELY EXCITED MACHINE NEEDS EXCITATION BY DC SUPPLY WHY NOT BY AC
what reason of line current and phase current in star connection and line current and phase current not equal in delta connection?
how we calculate the dick for a pole?
