25 + Interview Questions in Electrical Drive Systems And Components in Electric Drives Page 1 InterviewSolution

1.	In single-phase, RLE load, calculate the Peak inverse voltage using the data: (Vs)r.m.s = 9 V, f = 50 Hz,E = 40 V.(a) 52.2 V(b) 52.7 V(c) 59.7 V(d) 52.9 VI have been asked this question during an interview for a job.This interesting question is from Electrical Drive Systems and Components in division Electrical Drive Systems and Components of Electric Drives
Answer» Right answer is (b) 52.7 V Explanation: In a single PHASE, RLE load the peak inverse VOLTAGE ACROSS the THYRISTOR VT = Vm+E = 52.7 V.

Discussion

2.	Calculate the PIV for the Full-wave bridge rectifier if the peak value of the supply voltage is 50.(a) 72.5 V(b) 72.8 V(c) 70.7 V(d) 76.1 VI had been asked this question in a national level competition.Origin of the question is Electrical Drive Systems and Components topic in division Electrical Drive Systems and Components of Electric Drives
Answer» CORRECT answer is (c) 70.7 V The explanation is: The PEAK inverse voltage for the Full-wave BRIDGE rectifier is Vm = √2×230=70.7 V. The peak inverse is the maximum negative voltage across the thyristor.

Discussion

3.	Calculate the maximum frequency for ASCI using the data: R=1 kΩ, C=1 μF.(a) 250 Hz(b) 280 Hz(c) 300 Hz(d) 320 HzThe question was asked in an interview.My question is taken from Electrical Drive Systems and Components in chapter Electrical Drive Systems and Components of Electric Drives
Answer» The CORRECT choice is (a) 250 HZ Explanation: The minimum TIME period for ASCI is a 4×R×C=4×1×1×.001=4 MSEC. The total time is the sum of charging and discharging time. The maximum frequency is 1÷f=250 Hz.

Discussion

4.	Load interrupter operated at ________(a) No-load(b) Full load(c) Half of the full load(d) One-fourth of the full loadThe question was posed to me by my school principal while I was bunking the class.The question is from Electrical Drive Systems and Components in section Electrical Drive Systems and Components of Electric Drives
Answer» Right ANSWER is (b) FULL load The best I can explain: Load interrupter is used to avoid overloading CONDITIONS. It separates the under-stressed AREA from the line. It operates at full load.

Discussion

5.	Reactance relay is used in _______(a) Medium line(b) Short transmission line(c) Lossless line(d) Long transmission lineI have been asked this question during an online exam.My question is based upon Electrical Drive Systems and Components topic in portion Electrical Drive Systems and Components of Electric Drives
Answer» Right CHOICE is (B) Short transmission line Explanation: REACTANCE RELAY is used in a short transmission line. Reactance relay is independent of the resistance value. It protects the short transmission line from any fault.

Discussion

6.	Calculate the value of the fault impedance if the fault voltage is 2 V and fault current is 4 A.(a) .5 ohm(b) .2 ohm(c) .4 ohm(d) .6 ohmI had been asked this question in an online interview.This interesting question is from Electrical Drive Systems and Components topic in chapter Electrical Drive Systems and Components of Electric Drives
Answer» The correct ANSWER is (a) .5 OHM The best I can explain: The value of the fault impedance is the RATIO of fault voltage and fault current. It is EXPRESSED in OHMS. Z=V/I=2/4=.5 ohm.

Discussion

7.	Inter turn fault can be detected by using __________(a) Oil circuit breaker(b) Split phase relay(c) SF6 circuit breaker(d) Vertical breakerI got this question during a job interview.Question is taken from Electrical Drive Systems and Components topic in portion Electrical Drive Systems and Components of Electric Drives
Answer» Correct option is (b) Split phase relay To explain: Inter turn fault MAINLY OCCURS in the winding of the rotor SIDE of the alternator. They can be detected by USING the split-phase relaying technique.

Discussion

8.	Full form of LED is _____________(a) Light Emitting Diode(b) Light Emission Digital(c) Light Energy Diode(d) Light Energy DigitalThe question was posed to me in a national level competition.This interesting question is from Electrical Drive Systems and Components topic in chapter Electrical Drive Systems and Components of Electric Drives
Answer» The correct CHOICE is (a) Light Emitting DIODE Explanation: The full form of LED is a light-emitting diode. It converts light ENERGY into electrical energy. It works in the reverse bias region.

Discussion

9.	Mho relay is used in the medium transmission line.(a) True(b) FalseThis question was posed to me in a national level competition.My doubt is from Electrical Drive Systems and Components in portion Electrical Drive Systems and Components of Electric Drives
Answer» The correct answer is (b) False To explain: Mho RELAY is an INHERENT directional relay. It is used in the long TRANSMISSION line. It is less affected by power surges.

Discussion

10.	Relay is an electromechanical switch.(a) True(b) FalseI got this question by my college professor while I was bunking the class.My query is from Electrical Drive Systems and Components topic in section Electrical Drive Systems and Components of Electric Drives
Answer» The CORRECT answer is (a) True The BEST EXPLANATION: Relay is an electromechanical switch. It uses electrical SIGNALS as input and mechanical operation as an output.

Discussion

11.	Full form of PLC is ____________(a) Programmable Logic Controller(b) Programmable Language Controller(c) Peterson Language Counter(d) Programmable Logic CounterI got this question during an online interview.I'm obligated to ask this question of Electrical Drive Systems topic in division Electrical Drive Systems and Components of Electric Drives
Answer» Right answer is (a) PROGRAMMABLE LOGIC Controller The best EXPLANATION: The full form of PLC is Programmable logic controller. It is a computer CONTROL system that monitors input states and makes DECISIONS based upon a program to control output states.

Discussion

12.	Oil circuit breaker is mainly used in _____________(a) Synchronous machine(b) Induction machine(c) DC machine(d) TransformerThe question was posed to me in a job interview.Asked question is from Electrical Drive Systems in section Electrical Drive Systems and Components of Electric Drives
Answer» Correct CHOICE is (d) TRANSFORMER The BEST I can explain: Oil circuit breaker is mainly used in TRANSFORMERS. The oil ACTS a coolant for the transformer. When a fault occurs in the transformer oil decomposes in the gases.

Discussion

13.	Current Chopping is most severe in which one of the following?(a) Air Blast Circuit Breaker(b) Oil Circuit Breaker(c) Air Break Circuit Breaker(d) Vacuum Circuit BreakerThis question was posed to me in an internship interview.The doubt is from Electrical Drive Systems in section Electrical Drive Systems and Components of Electric Drives
Answer» Correct choice is (a) Air Blast Circuit BREAKER The explanation is: Current CHOPPING is most severe in the CASE of Air blast circuit breaker. Resistance switching is used to avoid the problem of current chopping.

Discussion

14.	Full form of PCC is ____________(a) Producer control center(b) Poor counter center(c) Power control center(d) Power coil counterThis question was posed to me by my college director while I was bunking the class.The question is from Electrical Drive Systems topic in portion Electrical Drive Systems and Components of Electric Drives
Answer» Correct CHOICE is (c) POWER CONTROL center For explanation I would say: The FULL form of PCC is Power control center. They receive power from the MAIN power distribution center.

Discussion

15.	Full form of MCC is ____________(a) Motor control center(b) Motor counter center(c) Machine control center(d) Motor coil counterI got this question during an interview.Question is from Electrical Drive Systems in chapter Electrical Drive Systems and Components of Electric Drives
Answer» CORRECT CHOICE is (a) Motor control center For explanation I WOULD say: The FULL FORM of MCC is Motor control center. It controls the power to system drives. There can many MCCs exist in an area.

Discussion

16.	Calculate the value measured by PMMC when a sinusoidal voltage signal V(t)=20sin(ωt) is applied to it.(a) 1 V(b) 2 V(c) 6 V(d) 0 VThis question was posed to me in examination.This intriguing question comes from Electrical Drive Systems topic in chapter Electrical Drive Systems and Components of Electric Drives
Answer» Right answer is (d) 0 V Best EXPLANATION: PERMANENT magnet moving COIL instrument measures the AVERAGE VALUE of the input signal. The average value of the sinusoidal signal is 0 V.

Discussion

17.	Full form of LSS is ____________(a) Line Surge Suppressors(b) Local Surge System(c) Local Surge Suppressors(d) Line SurgeSystemThe question was asked in final exam.This interesting question is from Electrical Drive Systems in chapter Electrical Drive Systems and Components of Electric Drives
Answer» RIGHT OPTION is (a) Line Surge Suppressors To explain: Full form of LSS is Line surge suppressors. They are used to PROTECT the semiconductor converter against voltage spikes PRODUCED in line.

Discussion

18.	The power conductor in electric trains is called a contact wire.(a) True(b) FalseThis question was posed to me in an online interview.My question is from Electrical Drive Systems topic in section Electrical Drive Systems and Components of Electric Drives
Answer» Correct option is (a) True To explain I would SAY: The supply CONDUCTOR in electric trains is also known as CONTACT wire. DRIVING MOTOR and power modulators are housed in the locomotive.

Discussion

19.	Who invented the first circuit breaker?(a) Albert Einstein(b) Thomas Edison(c) Nicola Tesla(d) Trent BoultThis question was posed to me in examination.I need to ask this question from Electrical Drive Systems topic in division Electrical Drive Systems and Components of Electric Drives
Answer» Correct answer is (b) THOMAS Edison Best EXPLANATION: Thomas Edison was the inventor of the circuit breaker. It was designed in 1879. It was an EARLY form of the circuit breaker.

Discussion

20.	When was the first train built?(a) 1804(b) 1810(c) 1814(d) 1820The question was asked in my homework.I want to ask this question from Electrical Drive Systems topic in portion Electrical Drive Systems and Components of Electric Drives
Answer» Correct OPTION is (a) 1804 The best I can EXPLAIN: Richard Trevithick built the FIRST train in 1804. It was a steam locomotive train that used to carry 10 tonnes of iron from one place to ANOTHER.

Discussion

21.	Calculate the coefficient of friction if the angle of inclination is 0°.(a) 2(b) 1(c) 4(d) 0The question was posed to me in an online interview.This intriguing question originated from Electrical Drive Systems in chapter Electrical Drive Systems and Components of Electric Drives
Answer» Correct CHOICE is (d) 0 Easy explanation: The coefficient of FRICTION is the tangent of the angle of the inclined plane. The VALUE of μ is the TAN(0°) = 0. The coefficient of friction depends on the nature of the SURFACE.

Discussion

22.	The frictional force always acts in the perpendicular direction of motion of the body.(a) True(b) FalseI have been asked this question during an online exam.My question is from Electrical Drive Systems in section Electrical Drive Systems and Components of Electric Drives
Answer» Correct OPTION is (b) False Explanation: The FRICTION of FORCE always acts in the OPPOSITE direction of the motion of the body. It is a non-conservative force. It helps in the motion of the body.

Discussion

23.	Full form of TVS is __________(a) Transient voltage suppression(b) Transient voltage surge(c) Total voltage surge(d) True voltage surgeThis question was posed to me by my college director while I was bunking the class.My question comes from Electrical Drive Systems topic in division Electrical Drive Systems and Components of Electric Drives
Answer» RIGHT option is (a) Transient voltage suppression Best EXPLANATION: The full form of TVS is Transient voltage suppression. It is one of the TYPES of light surge suppressors. It is USED to suppress transient VOLTAGES.

Discussion

24.	Calculate the value of the coefficient of static friction using the data: F=4 N, Normal force=16 N.(a) .24(b) .25(c) .15(d) .14I had been asked this question by my college professor while I was bunking the class.I'm obligated to ask this question of Electrical Drive Systems topic in chapter Electrical Drive Systems and Components of Electric Drives
Answer» Correct choice is (b) .25 Easy EXPLANATION: Coefficient of FRICTION is the RATIO of the friction force and normal force. It is dependent on the SMOOTHNESS of the SURFACE area. μ = 4÷16 = .25.

Discussion

25.	Calculate the minimum anode current required to turn off SCR if the latching current value is 2 A.(a) 2 A(b) 3 A(c) 4 A(d) 5 AThe question was asked in examination.My question comes from Electrical Drive Systems topic in chapter Electrical Drive Systems and Components of Electric Drives
Answer» Right ANSWER is (a) 2 A To EXPLAIN: The MINIMUM anode current required to turn off the SCR is the LATCHING current. The value of the latching current is 2 A.

Discussion

Explore topic-wise InterviewSolutions in .

Calculate the maximum frequency for ASCI using the data: R=1 kΩ, C=1 μF.(a) 250 Hz(b) 280 Hz(c) 300 Hz(d) 320 HzThe question was asked in an interview.My question is taken from Electrical Drive Systems and Components in chapter Electrical Drive Systems and Components of Electric Drives

Mho relay is used in the medium transmission line.(a) True(b) FalseThis question was posed to me in a national level competition.My doubt is from Electrical Drive Systems and Components in portion Electrical Drive Systems and Components of Electric Drives

Relay is an electromechanical switch.(a) True(b) FalseI got this question by my college professor while I was bunking the class.My query is from Electrical Drive Systems and Components topic in section Electrical Drive Systems and Components of Electric Drives

Oil circuit breaker is mainly used in _____________(a) Synchronous machine(b) Induction machine(c) DC machine(d) TransformerThe question was posed to me in a job interview.Asked question is from Electrical Drive Systems in section Electrical Drive Systems and Components of Electric Drives

Full form of MCC is ____________(a) Motor control center(b) Motor counter center(c) Machine control center(d) Motor coil counterI got this question during an interview.Question is from Electrical Drive Systems in chapter Electrical Drive Systems and Components of Electric Drives

Full form of LSS is ____________(a) Line Surge Suppressors(b) Local Surge System(c) Local Surge Suppressors(d) Line SurgeSystemThe question was asked in final exam.This interesting question is from Electrical Drive Systems in chapter Electrical Drive Systems and Components of Electric Drives

The power conductor in electric trains is called a contact wire.(a) True(b) FalseThis question was posed to me in an online interview.My question is from Electrical Drive Systems topic in section Electrical Drive Systems and Components of Electric Drives

Who invented the first circuit breaker?(a) Albert Einstein(b) Thomas Edison(c) Nicola Tesla(d) Trent BoultThis question was posed to me in examination.I need to ask this question from Electrical Drive Systems topic in division Electrical Drive Systems and Components of Electric Drives

When was the first train built?(a) 1804(b) 1810(c) 1814(d) 1820The question was asked in my homework.I want to ask this question from Electrical Drive Systems topic in portion Electrical Drive Systems and Components of Electric Drives

Calculate the coefficient of friction if the angle of inclination is 0°.(a) 2(b) 1(c) 4(d) 0The question was posed to me in an online interview.This intriguing question originated from Electrical Drive Systems in chapter Electrical Drive Systems and Components of Electric Drives

The frictional force always acts in the perpendicular direction of motion of the body.(a) True(b) FalseI have been asked this question during an online exam.My question is from Electrical Drive Systems in section Electrical Drive Systems and Components of Electric Drives

Calculate the minimum anode current required to turn off SCR if the latching current value is 2 A.(a) 2 A(b) 3 A(c) 4 A(d) 5 AThe question was asked in examination.My question comes from Electrical Drive Systems topic in chapter Electrical Drive Systems and Components of Electric Drives