1. The four point starter has three parallel paths.
2. In dc generators, the armature conductor generates emf by dynamic action.
3. To change the direction of rotation in a dc shunt motor, the field or armature connections must be interchanged.
4. Total flux is given per pole, Weber per pole.
5. To change the speed of the dc motor, the field aspect will have to be changed.
6. The speed of the dc motor is inversely proportional to the field flux.
7. A shunt generator 1500 RPM Is rotating and generating 250 volt emf. If the speed is 1200 rpm. If done, the emf generated will be 200 volts.
8. The formula to find the current taken by the armature of a dc motor is Ia=(V-Eb)/Ra
9. The formula to find the armature current of a shunt dc generator is Ia = IL + Ish
10. Power machines with low and medium voltage can be tested with a 500 volt magger. If the same machine is tested at the same time with 1000 volt magger in the same conditions, it will give lower readings.
11. The power written on the name plate of the motor is always the output power found on the shaft.
12. If the dc generator pulley rotates 2800 in 2 minutes, The speed of the dc generator will be 1400 rpm per minute.
13. Fleming's right hand rule is used to determine the direction of the generated electro motive force (EMF).
14. For safety, the fuse and switch of the test lamp should be fitted in phase wire.
15. A 220 volt, 10 hp DC shunt motor with an armature resistance of 0.2 ohms will take 1100 ampere current without a starter so a starter is required to control this current.
16. A dc The shunt generator is delivering 15 amperes at a terminal voltage of 230 volts. Its armature current will be 16 amperes with the shunt field resistance being 230 ohms.
17. If there is a break in the winding, it can be determined by continuity test. If an insulation test is done without paying attention to the brake, then it is not reliable because only some part of the winding will come under testing.
18. The formula for finding the shunt field current in a short shunt compound generator is- Ish=(V+Ise Rse)/Rsh
19. The excitation coil of the dc machine is wrapped around the pole.
20. If the dc machine is making 1800 revolutions per minute, then it will be 30 rps per second.
21. Lap winding is done in dc machines with high current and low voltage.
22. In power generation, the electro motive force (EMF) generated by the dynamic method is more important and useful than the emf generated by the static method. Because mechanical energy can be easily converted into electrical energy to produce it.
23. Insulation of mica is used between the commutator segment.
24. The speed, constant speed, load of the primemover of the shunt generator should be of specific properties to provide stable terminal voltage at different loads.
25. On long transmission lines, where the line drop increases with increasing load, the most suitable generator to meet them is the over compound generator.
26. It is not reliable to do a continuous test magger for winding because short circuit winding cannot be detected due to mega ohms reading of the magger.
27. A starter is necessary to start the dc motor as it limits the starting current to a safe value.
28. To generate electro motive force (EMF) in a conductor, it is necessary that the conductor or magnetic flux is moved towards each other so that the flux can be cut.
29. DC. Wave winding is done in machines with low current and high voltage.
30. If the dc generator is isolated, it is not necessary to have residual magnetism.
2. In dc generators, the armature conductor generates emf by dynamic action.
3. To change the direction of rotation in a dc shunt motor, the field or armature connections must be interchanged.
4. Total flux is given per pole, Weber per pole.
5. To change the speed of the dc motor, the field aspect will have to be changed.
6. The speed of the dc motor is inversely proportional to the field flux.
7. A shunt generator 1500 RPM Is rotating and generating 250 volt emf. If the speed is 1200 rpm. If done, the emf generated will be 200 volts.
8. The formula to find the current taken by the armature of a dc motor is Ia=(V-Eb)/Ra
9. The formula to find the armature current of a shunt dc generator is Ia = IL + Ish
10. Power machines with low and medium voltage can be tested with a 500 volt magger. If the same machine is tested at the same time with 1000 volt magger in the same conditions, it will give lower readings.
11. The power written on the name plate of the motor is always the output power found on the shaft.
12. If the dc generator pulley rotates 2800 in 2 minutes, The speed of the dc generator will be 1400 rpm per minute.
13. Fleming's right hand rule is used to determine the direction of the generated electro motive force (EMF).
14. For safety, the fuse and switch of the test lamp should be fitted in phase wire.
15. A 220 volt, 10 hp DC shunt motor with an armature resistance of 0.2 ohms will take 1100 ampere current without a starter so a starter is required to control this current.
16. A dc The shunt generator is delivering 15 amperes at a terminal voltage of 230 volts. Its armature current will be 16 amperes with the shunt field resistance being 230 ohms.
17. If there is a break in the winding, it can be determined by continuity test. If an insulation test is done without paying attention to the brake, then it is not reliable because only some part of the winding will come under testing.
18. The formula for finding the shunt field current in a short shunt compound generator is- Ish=(V+Ise Rse)/Rsh
19. The excitation coil of the dc machine is wrapped around the pole.
20. If the dc machine is making 1800 revolutions per minute, then it will be 30 rps per second.
21. Lap winding is done in dc machines with high current and low voltage.
22. In power generation, the electro motive force (EMF) generated by the dynamic method is more important and useful than the emf generated by the static method. Because mechanical energy can be easily converted into electrical energy to produce it.
23. Insulation of mica is used between the commutator segment.
24. The speed, constant speed, load of the primemover of the shunt generator should be of specific properties to provide stable terminal voltage at different loads.
25. On long transmission lines, where the line drop increases with increasing load, the most suitable generator to meet them is the over compound generator.
26. It is not reliable to do a continuous test magger for winding because short circuit winding cannot be detected due to mega ohms reading of the magger.
27. A starter is necessary to start the dc motor as it limits the starting current to a safe value.
28. To generate electro motive force (EMF) in a conductor, it is necessary that the conductor or magnetic flux is moved towards each other so that the flux can be cut.
29. DC. Wave winding is done in machines with low current and high voltage.
30. If the dc generator is isolated, it is not necessary to have residual magnetism.