Electrical Engineering Interview Questions
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a)In a 3-phase 4-wire circuit, a circuit breaker is selected to protect the circuit whose highest fault level is 6.6 MVA. Determine the required minimum breaking capacity in kA. (Note: Covert 3-phase power in terms of kA to find answer.) b)Using the below, determine the required minimum making capacity in kA as a “peak value”. Rate breaking capacity (Icn) ka: Icn<= 1.5 Factor = 1.41 1.5

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1. A 380 / 220 V r.m.s. 3-phase 4-wire circuit carries loads of 8 + j8.1 ohm; 4 + j4.1 ohm; and 2 +j2.1 ohmin the three phases respectively. The length of the circuit is 100 m, and the resistivity of the phase conductors is 0.0005 Ω/m. The neutral conductor is of the same size as the phase conductors. a) Select a reference angle 0for the first phase. Then write down the three phase voltages in both polar format and complex number format. b) Make appropriate assumptions, and take temperature effects on resistance is insignificant. Calculate the currents in the three phases. (Note: Determine conductor resistance, and apply Kirchhoff’s Voltage Law) Based on the result, suggest a main switch rating for the circuit. c) Show your preferred direction of neutral current in a diagram, and then determine its value. (Note: Apply superposition principle, and Kirchhoff’s Current Law) Use its magnitude to show that in this circuit, the unbalanced load may increase the voltage drop in some of the phases. (Note: Also observe the common volt drip in neutral) State your assumptions, if there are any. d) Suddenly the neutral wire of the circuit is broken. Estimate the new currents in the first phase, i.e. Phase L1. State your assumptions, if there are any.

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Why capacitor bank ratting Kvar?

1 1905

How to define Kirchhoff current law and voltage law along with simply examples.

1209

Merz-Price circulating current principles is more suitable for

Student,

1 4782

what kinds of Transformer oil grade is better for power transformer ?

KSRM Steel Plant,

1163

Why is voltage is required to be within permissible range for an electrical equipment?

1259

R=*¶ l/a

1156

main difference between ac and dc?

Classic Network,

1198

Why do you use an isolator on both sides of the circuit breaker? ( shortly answer)

2 2148

how generator load test is conducted?what are the steps?

1127

what are the steps involved in generator load test?

1090

what is the most permissible winding temp when we conducting a generator load test?(condition no load)

1221

how i define power factor when some one ask me ,,,,,what is power factor ,,,,,pleas define it simple. (pleas dont use these worlds ,,the difrence bitween apparent power and actual power is power facter )

1 1552

i have 500 amp inductive load of motors ,,,pleas tell me how can i calculate for capacitor bank for improving my power factor to 99 .....calcullations for capacitor bank,,,,

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Un-Answered Questions { Electrical Engineering }

Dear sir, iam completed iti ncvt electrician 2000-2002 & diploma electrical eng completed 2008-2010 distance education in rvd university, still i got B licences only but my working company want C licences, how to i get c licencese pls reply me iam in critical situation thank you karthick 9841637803

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I want to do a mini project. Now I'm studying in 6th semis tor EEE Engineering.

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I am doing apprenticeship training at HT switch yard in NLC. How can i get electrical c license. ??? What r the rules for getting it as an apprentice? ??

1355


what is the synchronous timer ? and it applications.

1893


trasnfarmaer core make

1522






Please define ohm’s law for a.c (alternating current)?

629


Explain the working of any one cutting machine

655


what is the principle of the single phase energy meter? and,what is the advantages and disadvantages of single phase energy meter?

3951


What is mean by Sensitive Earth fault & what are the effects

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when will be the iocl interview results i faced interview on 8th september 2008 iam from electrical branch i faced interview for the post of electrical engineer??????????????????????//

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132/6.6𝚔𝚟 𝚝𝚛𝚊𝚗𝚜𝚏𝚘𝚛𝚖𝚎𝚛 𝚗𝚎𝚞𝚝𝚛𝚊𝚕 𝚑𝚊𝚜 𝚘𝚗𝚎 𝚎𝚊𝚛𝚝𝚑 𝚙𝚒𝚝 𝚍𝚎𝚍𝚒𝚌𝚊𝚝𝚎𝚍. 𝙸'𝚟𝚎 𝚊𝚗𝚘𝚝𝚑𝚎𝚛 𝚝𝚛𝚊𝚗𝚜𝚏𝚘𝚛𝚖𝚎𝚛 𝚘𝚏 6.6𝚔𝚟/415𝚟 𝚌𝚊𝚗 𝙸 𝚌𝚘𝚗𝚗𝚎𝚌𝚝 𝚗𝚎𝚞𝚝𝚛𝚊𝚕 𝚝𝚘 𝚜𝚊𝚖𝚎 𝚎𝚊𝚛𝚝𝚑 𝚙𝚒𝚝 𝚊𝚜 𝚘𝚏 13/6.𝚔𝚟 𝚝𝚛𝚊𝚗𝚜𝚏𝚘𝚛𝚖𝚎𝚛?? 𝙸𝚏 𝙽𝚘.. 𝚃𝚑𝚎𝚗 𝚠𝚑𝚢??

573


he compression ratio for a petrol engine generally lies between

695


Is it possible to connect a safety device in to parallel?

1545


STATE WORKING OF VACCUM CIRCUIT BRAKER?

1459


Earth bits close or open. Which is correct

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