Interview Question Asked Interview Question for Electrical Engineering

  Digital Electronics 

1. Mention the working regions of transistor as a switch.What is Schotky diode?
2. Explain excess 127 format
3. Differentiate between combinational and sequential circuits
4. What is a TTL floating input equivalent to?
5. What is active high and active low logic?
6. How is race around condition eliminated in master slave JK flip flop?
7. Differentiate between latch and flip flop
8. Give a simple method for frequency division.Realise a half adder circuit
9. Uses of Schmidt trigger circuits. How can you eliminate noise in digital circuits?
10. Explain low pass filter

  Analog Electronics  

1. What is Barkhausen criterion?Draw RC phase shift oscillator and explain
2. How is Laplace transform useful in solving analog circuits?
3. Why is common collector configuration not used for amplifier?
4. What is ripple factor?What is hard saturation in transistors?
5. What is thermal runaway?What do you mean by rms value of current?
6. Practical applications of variable resistance What is form factor?
7. Does an oscillator have an input? If so, draw it

  Power System Engineering 

1. It is always advisable not to keep your feet apart when standing in a substation yard. Why? What is step potential?
2. Does corona has any advantage in power system?
3. What are lightning arrestors?
4. What are the different power system losses and how can it be eliminated?
5. What is the criterion for selection of system voltage?
6. What is the difference between an insulator and a dielectric?
7. What is bus bar? Differentiate between an insulator and a dielectric
8. Explain the principle of operation of a relay and a circuit breaker?
9. What is skin effect? Why is voltage stepped up before transmission?
10. Explain transmission and distribution systems
11. What are the standard transmission and distribution voltages
12. How are turbines selected to be installed in a generating station?
13. Which is better 50 Hz supply or 60 Hz? Explain
14. What are the disadvantages of low power factor?
15. What is grading of a cable?
16. Explain the power rating of a bulb, say 60W, what if the voltage changes?
17. Why is the earth pin in a 3-pin plug the longest and the thickest?
18. Is there any difference between circuit breakers and isolators?
19. What is IDMT? What is the principle?
20. What is SCADA?
21. Which is the oldest generating station in Kerala?
22. Which type of luminance has greater visibility- GLS or FL?
23. Why do we use a trap draw circuit?
24. What is power line communication?
25. What are traveling waves?
26. How can you decrease the harmonics in a waveform?

  Electrical machines 

1. Why are tertiary windings used in transformers?
2. What is the wattage of a ‘zero-watt’ bulb?
3. Which type of winding would you choose for low voltage high current generators and why?
4. Why do series motors have high starting torque?
5. What is regenerative braking? What are its advantages?
6. What happens if armature and field coils of a generator are interchanged and used? Why are induction motors more widely used?
7. What are brushless alternators? What is plugging of an induction motor?
8. What are equalizer rings used for?
9. Which is more dangerous- shock due to ac or dc?
10. How is the alternator synchronized to the main busbar?
11. What are the applications of servomotor?
12. How do you specify the rating of a transformer?
13. What is specified in synchronous watts?
14. How are lines affected by synchronous operation?
15. Which is the motor used in fans?
16. What is the purpose of compensating winding? What are dummy coils?
17. Why is transformer rating specified in kVA?
18. What is phase swinging? What is phase margin?

  Electrical Measurements  

1. What are integrating instruments?
2. Differentiate MC and MI instruments

  Power Electronics  

1. How do you convert fixed ac to variable ac?
2. Can an inverter be used as a converter? How?
3. Explain the effect of a free wheeling diode.