Top 100+ Electrical Engineering Interview Questions And Answers
Question 1. What Is The Difference Between A Verilog Task And A Verilog Function?
Answer :
The following policies distinguish responsibilities from capabilities:
A feature shall execute in one simulation time unit; a project can comprise time-controlling statements.
A function cannot enable a mission; a challenge can enable other responsibilities or features.
A characteristic shall have as a minimum one input kind argument and shall no longer have an output or inout kind argument;a project will have 0 or greater arguments of any type.
A function shall return a unmarried fee; a venture shall no longer go back a cost.
Question 2. Explain The Differences Between "direct Mapped", "absolutely Associative", And "set Associative" Caches ?
Answer :
If every block has best one area it could seem in the cache, the cache is stated to be direct mapped. The mapping is generally (block-body address) modulo (variety of blocks in cache).
If a block may be located everywhere inside the cache, the cache is stated to be fully associative.
If a block may be positioned in a limited set of places within the cache, the cache is said to be set associative. A set is a set of two or greater blocks within the cache. A block is first mapped onto a fixed, after which the block can be positioned anywhere within the set. The set is typically chosen with the aid of bit selection; this is, (block-frame address) modulo (number of sets in cache). If there are n blocks in a hard and fast, the cache placement is called n-way set associative.
Electrical and Electronics Engineering Interview Questions
Question three. What Is Electric Traction?
Answer :
Electric traction method the usage of the electric electricity for traction device (i.E. For railways,trams, trolleys and so on).
Electric traction means use of the electricity for railways,trams, trolleys etc. Now a days, magnetic traction is likewise used for bullet trains.And basically dc cars are used for electric traction structures.
Question four. How Can You Startup The 40w Tube Lite With 230v Ac/dc Without Using Any Choke/coil?
Answer :
It’s possible by way of Electronic chokes,otherwise it’s now not possible to ionize the debris in tube mild with regular voltage.
Question 5. What Is “pu” In Electrical Engineering?
Answer :
Pu stands for in line with unit and this will be used in single line diagram of energy distribution and it's far like a big electrical circuit without a of additives (generators, transformers, hundreds) with distinct rankings (in MVA and KV). To carry all the ratings into commonplace platform we use pu idea wherein, in general largest MVA and KV rankings of the component is considered as base values, then all different factor rankings will get lower back into this foundation.Those values are called as pu values.
Programmable Logic Controller (PLC) Interview Questions
Question 6. Operation Carried Out In Thermal Power Stations?
Answer :
The water is received inside the boiler and the coal is burnt in order that steam is acquired this steam is authorized to hit the turbine , the turbine which is coupled with the generator generates the energy.
Question 7. Why Link Is Provided In Neutral Of An Ac Circuit And Fuse In Phase Of Ac Circuit?
Answer :
Link is provided at a Neutral not unusual point in the circuit from which numerous connection are taken for the man or woman manage circuit and so it's far given in a hyperlink form to resist excessive Amps. But inside the case of Fuse in the Phase of AC circuit it is designed such that the fuse score is calculated for the unique circuit (i.E load) only.So if any malfunction take place the fuse connected in the specific control circuit on my own will blow off.
BHEL Interview Questions
Question eight. How Tube Light Circuit Is Connected And How It Works?
Answer :
A choke is hooked up in one stop of the tube mild and a starter is in collection with the circuit. When supply is provided ,the starter will interrupt the supply cycle of AC. Due to the surprising alternate of deliver the chock will generate around 1000volts . This volt will capable of to break the electrons in the tube to make electron glide. As soon as the current passes through the tube the starter circuit will be out of element. Now there's no alternate of deliver reasons choke voltage normalized and act as limit the modern-day.
Question nine. What Is Marx Circuit?
Answer :
It is used with generators for charging some of capacitor in parallel and discharging them in collection.It is used while voltage required for testing is better than the to be had
Control Systems-Electrical Engineering Interview Questions
Question 10. What Is Encoder, How It Function?
Answer :
An encoder is a tool used to alternate a signal (together with a bitstream) or information right into a code. The code may additionally serve any of a number of functions including compressing data for transmission or garage, encrypting or adding redundancies to the enter code, or translating from one code to another.
This is usually finished by a programmed set of rules,mainly if any part is virtual, whilst maximum analog encoding is executed with analog circuitry.
Question eleven. What Are The Advantages Of Speed Control Using Thyristor?
Answer :
Advantages :
Fast Switching Characterstics than Mosfet, BJT, IGBT.
Low price.
Higher Accurate.
Electrical Machines Interview Questions
Question 12. Why Human Body Feel Electric Shock ?? N In An electric powered Train During Running , We Did Nt Feel Any shock ? Why?
Answer :
Unfortunately our frame is a pretty true conductor of power, The golden rule is Current takes the bottom resistant direction if you have insulation to our feet as the circuit isn't whole (carrying rubber footwear which doing some maintenance is recommended as our shoes is a excessive resistance direction no longer tons modern-day flows thru our frame).The electric teach is properly insulated from its electrical system.
Electrical and Electronics Engineering Interview Questions
Question 13. What Is The Principle Of Motor?
Answer :
Whenever a modern-day carrying conductor is positioned in an magnetic area it produce turning or twisting movemnt is known as as torque.
Question 14. Why, When Birds Sit On Transmission Lines Or Current Wires Doesn’t Get Shock?
Answer :
Its real that if birds touch the unmarried one line (section or impartial) they don’t get electric surprise… if birds contact 2 lines than the circuit is closed and that they get electrical surprise.. So if a human contact single one line(phase) then he doesn’t get surprise if he is in the air (now not touching – standing at the floor if he's standing at the floor then touching the road (section) he'll get a surprise due to the fact the ground on what we standing is like line (ground mattress – like neutral)? And within the most of electrical traces the neutral is grounded..So which means that human who contact the line closes the circuit among phase and neutral.
Question 15. What Is Meant By Armature Reaction?
Answer :
The effect of armature flu to major flux is referred to as armature reaction. The armature flux might also support primary flux or opposes fundamental flux.
DC motor Interview Questions
Question sixteen. What Happen If We Give 220 Volts Dc Supply To D Bulb R Tube Light?
Answer :
Bulbs [devices] for AC are designed to operate such that it gives excessive impedance to AC deliver. Normally they have low resistance. When DC supply is implemented, due to low resistance, the cutting-edge through lamp could be so excessive that it can harm the bulb element.
Question 17. Which Motor Has High Starting Torque And Staring Current Dc Motor, Induction Motor Or Synchronous Motor?
Answer :
DC Series motor has high starting torque. We cannot begin the Induction motor and Synchronous cars on load, however can't start the DC series motor without load.
Induction Motors Interview Questions
Question 18. What Is Acsr Cable And Where We Use It?
Answer :
ACSR manner Aluminium conductor metal strengthened, this conductor is utilized in transmission & distribution.
Programmable Logic Controller (PLC) Interview Questions
Question 19. What Is Vaccum Currcuit Breaker.Outline With Cause And Where Be Use It Device?
Answer :
A breaker is normally used to interrupt a ciruit. Whilst breaking the circuit, the touch terminals will be separated. At the time of seperation an air gap is formed in among the terminals. Due to current modern-day glide the air inside the gap is ionised and results inside the arc. Numerous mediums are used to quench this arc in respective CB’s. However in VCB the medium is vaccum fuel. Since the air in the CB is having vaccum strain the arc formation is interrupted. VCB’s may be used upto kv.
Question 20. What Will Happen When Power Factor Is Leading In Distribution Of Power?
Answer :
If their is high power aspect, i.E if the energy factor is near one:
losses in form of heat will be reduced,
cable becomes much less cumbersome and easy to hold, and very cheap to have enough money, &
it additionally reduces over heating of tranformers.
Electrical Power System Interview Questions
Question 21. What Is The One Main Difference Between Ups & Inverter ? And Electrical Engineering & Electronics Engineering ?
Answer :
uninterrupt power deliver is in particular use for brief time .Means in step with u.S.A.VA it gives backup.
Usais also two sorts :
on-line.
Offline.
Online united stateshaving high volt and amp for long time backup with with excessive dc voltage.But americabegin with 2v dc with 7 amp. However inverter is startwith 2v,24,dc to 36v dc and 20amp to 80amp battery with long term backup.
Question 22. What Is 2 Phase Motor?
Answer :
A segment motor is a motor with the the beginning winding and the strolling winding have a segment split.
E.G?ac servo motor.Where the auxiliary winding and the control winding have a phase cut up of 90 diploma.
Question 23. What Is Power Factor? Whether It Should Be High Or Low? Why?
Answer :
Power factor ought to be excessive a good way to get smooth operation of the gadget.Low electricity element manner losses might be extra.It's miles the ratio of actual electricity to obvious power. It needs to be preferably 1. If it's far too low then cable over heating & equipment overloading will arise.
If it's miles extra than 1 then load will act as capacitor and starts offevolved feeding the source and could reason tripping.(if pf is terrible ex: zero.17 to fulfill actual power load has to draw greater contemporary(V steady),bring about extra losses if pf is right.
Ex: 0.Ninety five to satisfy actual electricity load has to attract much less cutting-edge(V constant),bring about less losses).
Question 24. There Are A Transformer And An Induction Machine. Those Two Have The Same Supply. For Which Device The Load Current Will Be Maximum? And Why?
Answer :
The motor has max load cutting-edge evaluate to that of transformer because the motor consumes actual power.. And the transformer is best generating the running flux and its now not ingesting.. Subsequently the burden cutting-edge within the transformer is due to center loss so it is minimal.
BHEL Interview Questions
Question 25. Explain The Working Principal Of The Circuit Breaker?
Answer :
Circuit Breaker is one which makes or breaks the circuit.It has two contacts specifically constant touch & moving touch.Below normal circumstance the moving contact comes in touch with fixed touch thereby forming the closed touch for the drift of cutting-edge. During bizarre & faulty situations(while present day exceeds the rated price) an arc is produced between the constant & transferring contacts & thereby it paperwork the open circuitArc is extinguished by using the Arc Quenching media like air, oil, vaccum and many others
Question 26. How Many Types Of Colling System It Transformers?
Answer :
ONAN (oil natural,air herbal).
ONAF (oil natural,air forced).
OFAF (oil forced,air forced).
ODWF (oil direct,water forced).
OFAN (oil pressured,air pressured).
Question 27. What Is The Function Of Anti pumping In Circuit Breaker?
Answer :
while breaker is near at one time by means of near push button,the anti pumping contactor prevent re close the breaker with the aid of close push button after if it already close.
Control Systems-Electrical Engineering Interview Questions
Question 28. What Is Stepper Motor.What Is Its Uses?
Answer :
Stepper motor is the electrical machine which act upon enter pulse implemented to it. It is one form of synchronous motor which runs in steps in both direction as opposed to running in complete cycle.So, in automation elements it's far used.
Question 29. Why The Capacitors Works On Ac Only?
Answer :
Generally capacitor gives limitless resistance to dc components(i.E., block the dc additives). It lets in the ac components to skip through.
Question 30. What Happens If I Connect A Capacitor To A Generator Load?
Answer :
Connecting a capacitor across a generator continually improves energy factor,but it will assist relies upon up at the engine potential of the alternator,different wise the alternator may be over loaded because of the more watts fed on because of the development on pf. Secondly, don’t connect a capacitor across an alternator whilst it is selecting up or with none other load.
Question 31. What Is The Difference Between Surge Arrestor And Lightning Arrestor?
Answer :
LA is mounted outdoor and the effect of lightning is grounded,where as surge arrestor set up inner panels comprising of resistors which consumes the strength and nullify the impact of surge.
Question 32. Why Use The Vcb At High Transmission System ? Why Can’t Use Acb?
Answer :
Actually the factor is vacuum has high arc queching assets compare to air due to the fact in VCB ,the die electric powered strengths identical to 8 times of air . That is y usually vaccum used as in HT breaker and air used as in LT .
Question 33. Difference Between A Four Point Starter And Three Point Starter?
Answer :
The shunt connection in 4 point stater is furnished one by one form the line in which as in three point stater it is connected with line that is the disadvantage in 3 point stater.
Electrical Machines Interview Questions
Question 34. What Is An Exciter And How Does It Work?
Answer :
There are two sorts of exciters, static exciter and rotory exciter.
Cause of excitor is to deliver the excitation dc voltage to the fixed poles of generator.
Rotory excitor is an additional small generator installed on the shaft of most important generator. If it's miles dc generator, it'll deliver dc to the rotory poles thru slip ring and brushes(traditional alternator).
If it is an ac excitor, out positioned of ac excitor is rectified with the aid of rotating diodes and deliver dc to predominant constant poles.Ac excitor is the ac generator whose area winding are stationary and armature rotates. Initial voltage is built up by using residual magnetism.It gives the beginning torque to the generator.
Question 35. What Is Automatic Voltage Regulator(avr)?
Answer :
AVR is an abbreviation for Automatic Voltage Regulator.It is critical component in Synchronous Generators, it controls theoutput voltage of the generator by using controlling its excitation modern. Thus it can manage the output Reactive Power of the Generator.
Question 36. Enlist Types Of Dc Generator?
Answer :
D.C.Generators are classified into sorts:
separatly exicted d.C.Generator.
Self exicted d.C.Generator.
That's similarly labeled into?1)collection 2)shunt and compound(that is further categorised into cumulative and differential).
DC motor Interview Questions
Question 37. Why Syn. Generators Are Used For The Production Of Electricity?
Answer :
Synchronous machines have functionality to paintings on one of a kind power aspect(or say one of a kind imaginary pow various the sector emf. Hence syn. Generators are used for the manufacturing of electricity.
Question 38. What Is The Difference Between Synchronous Generator & Asynchronous Generator?
Answer :
In simple, synchronous generator supply’s each energetic and reactive power but asynchronous generator(induction generator) supply’s only energetic strength and examine reactive power for magnetizing.This sort of turbines are used in windmills.
Question 39. What Is Boucholz Relay And The Significance Of It In To The Transformer?
Answer :
Boucholz relay is a device which is used for the safety of transformer from its internal faults, it is a gasoline based relay. Whenever any inner fault occurs in a transformer, the boucholz relay at once offers a horn for a while, if the transformer is remoted from the circuit then it forestall its sound itself other sensible it trips the circuit by using its own tripping mechanism.
Question 40. What Is Sf6 Circuit Breaker?
Answer :
SF6 is Sulpher hexa Flouride fuel.. If this gas is used as arc quenching medium in a Circuitbreaker method SF6 CB.
Induction Motors Interview Questions
Question forty one. What Is Frantic Effect?
Answer :
Output voltage is greater than the input voltage or receiving cease voltage is more than the sending end voltage.
Question forty two. What Is Meant By Insulation Voltage In Cables? Explain It?
Answer :
It is the belongings of a cable with the aid of virtue of it may withstand the applied voltage without rupturing it's miles called insulation degree of the cable.
Electrical Power System Interview Questions
Question forty three. What Are The Advantages Of Star Delta Starter With Induction Motor?
Answer :
Resolution:
The foremost benefit of the use of the famous person delta starter is discount of current for the duration of the starting of the motor.Starting current is decreased to 3four times Of modern-day of Direct on line beginning.
Hence the starting contemporary is reduced , the voltage drops during the starting of motor in systems are decreased.
Question 44. Why Delta Star Transformers Are Used For Lighting Loads?
Answer :
For lights loads, neutral conductor is ought to and hence the secondary need to be famous person winding. And this lights load is constantly unbalanced in all 3 levels. To limit the cutting-edge unbalance in the primary we use delta winding inside the number one. So delta / megastar transformer is used for lighting fixtures loads.
Question 45. What Is Meant By Regenerative Braking?
Answer :
When the deliver is cutt off for a running motor, it nonetheless keep walking due to inertia. In order to forestall it fast we place a load(resitor) across the armature winding and the motor should have maintained continuous subject deliver. In order that lower back e.M.F voltage is made to use across the resistor and due to load the motor stops quick.This sort of breaking is known as as “Regenerative Breaking”.
