(B)- Indicate whether the following statements are true or false and correct the false statements 1-In d.c shunt motor the main advantage of rheostatic control method, the speed up to zero is possible The imaginary component of no load current for transformer is responsible for the consumption of iron loss 3- The speed of d.c series motor is decreased if the armature current is increased 4 The armature voltage of d.c series generator is not affected by load current ane afland

(B)- Indicate whether the following statements are true or false and correct the false statements 1-In d.c shunt motor the main advantage of rheostatic control method, the speed up to zero is possible The imaginary component of no load current for transformer is responsible for the consumption of iron loss 3- The speed of d.c series motor is decreased if the armature current is increased 4 The armature voltage of d.c series generator is not affected by load current ane afland

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter33: Single-phase Motors

Section: Chapter Questions

Problem 32RQ

See similar textbooks

Similar questions

er C ai Exa (B)- Select the correct answer for the alternatives given. 1- A d.c. shunt motor is running with certain load. The effect of adding an external resistance field circuit is to a)-reduce the motor speed, b)-increase the motor speed, c)- stop the motor d)- reduce the armature current of the motor 2- The copper loss and iron loss of transformer at half load are 1600 w and 5000w respectively. The copper loss and iron loss at full load will be respectively. a)-(3200 w and 10000w), b)- (6400 w and 5000 w), c)-(6400 w and 10000w), d)- (3200 w and 1250w) Way t 3- The secondary winding of which of the following transformer is always kept close b)- auto-transformer, c)- current transformer, a)-power transformer d)-distribution transformer 4- A 6-pole lap wound de shunt generator is supplying 295 A to load. The field current of generator is 5A. The current parallel path is a)-300A 245)-145A b)- 150A, c)- 50A باب الثاني
2- A 4-pole, wave-wound d.c. shunt generator has an armature winding consisting of 300 turns each of 0.0020. The armature resistance is a) 0.152 b)0.62 c) 0.30 d) none of above
Please solve this problem step by step and illustrate your answer properly. Write your answer in a piece of paper please. Box the final answer.
1.Two identical shunt generators running in parallel, each with armature resistance of 0.02 ohms and field resistance of 50 ohms. The combined load current is 5000A. The field are so excited that the generated voltages of one machine is 610V and the other is 600V. The terminal voltage of this parallel combination will be. www Ish1 Rh1 a.350-360 V b.450-460 V c. 550-560V Rat www az G₂ Raz 5000 A Ish2
Consider the following statements regarding the design of the distributed armature winding in a three-phasealternator:1. It reduces the phase belt harmonics.2. It increases utilization of armature iron and copper.3. It increases rigidity and mechanical strength of the winding.4. It reduces copper in the overhand of the winding. Which of the statements are correct? a. 1,3 and 4b. 2,3 and 4c. 1,2 and 3d. 1,2,3 and 4
A shunt DC generator has no load terminal voltage of 140V. Armature resistance is 1ohm and shunt field resistance is 50ohms. Calculate: (i) Induced voltage (ii) A load is now connected to the terminals that starts drawing 2A current and terminal voltage drops to 130V. Calculate the new value of the induced voltage Make sure to draw equivalent circuits for (i) and (ii)
In a DC generator, the effect of armature reaction on the main field is to * reverse it O distort it O reduce it O both (b) and (c)
4. e principle of operation of a 3-phase. Induction motor is most similar to that of a (a) synchronous motor (b) DC motor (c) transformer with a shorted secondary (d) SPIM 5. 500 kW, 3-phase, 440 volts, 50 Hz, A.C. induction motor has a speed of 960 r.p.m. on full load. The machine has 6 poles. The slip of the machine will be (a) 0.01 (b) 0.02 (c) 0.03 (d)0.04 6. A centrifugal switch is used to disconnect 'starting winding when motor has (a) picked up about 50 to 75 per cent of rated speed (b) picked up about 10 to 15 per cent of rated speed (c) run for about 1 minute (d) run for about 5 minutes 7- A 6-pole, 50-Hz, 3-0 induction motor is running at 950 rpm and has rotor Cu loss of 6 kW. Its rotor input is......kW (a) 120 (b) 60 (c) 6.3 (d) 66 8- The number of slip rings on a squirrel cage induction motor is usually (a)Two (b) Three (c) Four (d) None
Q13-Explain briefly the following questions 1- What is the purpose of laminating the core in a transformer? 2- What two important effects are produced by armature reaction? 4- What are the differences between the components of a dc generator and a dc motor? 5-How to solve the Commutation Problem in d.c machines 6-List the various methods of flux control for d.c series motors, and draw a neat diagram of one method
Q choose the correct answer: 1-Brushless excitation system consisting of.... a- Stator field winding and power diodes b-stator and rotor field winding and capacitor c- stator and rotor field winding and capacitor d- Everything mentioned in the options 2- Voltage generated per phase in an alternator is proportional to a- Flux per pole b- Number of turns in armature c-Winding factors d- Everything mentioned in the options e- Frequency of waveform 3- If input mech. Power of SG constant, the functionality of AVR is a- Control flux of rotor b-Control terminal voltage c- Control flux and terminal voltage d-Control Load angle
Indicate whether the following - * statement are true or false False True In a dc machine for the same value of Z, N, O armature , e.m.f. is more with wave winding than with lap winding
Q2- Indicate whether the following statements are true or false and correct the false statements 1- The brushes of d.c machine always are placed at the magnetic neutral axis 2- The field current of d.c shunt generator is not affected by load current. 3-The armature voltage of d.c series generator is not affected by load current. 4- A lap winding is most suitable for higher voltage rating machines 5- In de generator, the critical resistance can be increased by increasing its speed 6-In LAP winding the front pitch equal to (yr Ye- yb). 7- The speed of d.c series motor is decreased if the armature current is decreased 8- The compensating winding carrying the field current 9- By tapping field method, the speed of d.c series motor can be controlled below rated value 10- To solve the Commutation Problem in small machines, this can be achieved by increasing the brush width