Interview Questions Answers in Electrical Engineering

Questions / { shyam }

Questions Answers Category Views Company eMail

why microprocessors are named as 8085 ,8086 etc? what's the reason for this???

15 Electrical Engineering 39927

When charging a 20 MVA , 33kV/6.6kV transformer through
regulated (0-6.6 kV or 0-33 kV) source on no load , what
will be the maximum current drawn by transformer from
source and what sould be the source capacity.

Answer

max. current drawn is 606.1 amps

Is This Answer Correct ?

2 Yes

6 No

Question { ABB, 50736 }

What is the difference when selecting a cable between AC
and DC current?

Answer

for selecting a cable for ac,its rms rating is to be
considered while for selecting cable for dc,its average or
dc value is to be considered.

Is This Answer Correct ?

15 Yes

3 No

Question { SVIT, 14787 }

in india ac frequency is 50hz, but in foreign countries it
is 60hz,whwt is the reason

Answer

first of all there is one thing that there is no power loss
due to reactive elements.so when capacitive or inductive
elements are used there is no any power losses there .
this 50 hz freq. is adopted to reduce the long transmission
losses......and also to reduce the voltage drop between
sending end voltage and receiving end voltage.

Is This Answer Correct ?

4 Yes

6 No

Question { 6468 }

If i switch on a transformer but with no load connected to
the secondary path.Is the transformer will burn?

Answer

no way....there is no possibilty of burning down ....
ya there is iron loss will occur n negligible copper loss in
primary bt it will not burn down d transformer.....

Is This Answer Correct ?

9 Yes

0 No

Question { HCL, 39927 }

why microprocessors are named as 8085 ,8086 etc?
what's the reason for this???

Answer

thanks sir,at least u tried to explain me the things that our lecturers haven't explained.
thanx....

Is This Answer Correct ?

11 Yes

7 No

Question { Essar, 5723 }

How can we calculate the power factor of an electrical
appliance ?

Is there any formula ? Is there any meter around to
calculate it ? And how to use that meter ? thanks

Answer

power factor can be calculated by formula =kw/kva.
there are power factor meters avilable to measure the power
factor direclty of an equipment.

Is This Answer Correct ?

4 Yes

0 No

Question { NTPC, 10886 }

What is the relation between the Peripheral speed(N) , no.of
poles(P) and diameter(D) of a cylindrical rotor alternator ?

Answer

then i hope u can also answer why speed of salient pole
motor is less than cylindrical pole motor?
itz because for bigger diameter rotor higher speed is nor
possible as it experiences greater centrifugal force.

Is This Answer Correct ?

1 Yes

2 No

Question { 10986 }

in 3 phase (4 wire) star connection - is current pass through
neutral??

Answer

In case of a fault or in case of unbalanced load,there is
some leakage current which flows through the neutral.
so there is some current through the neutral but not in all
conditions.

Is This Answer Correct ?

4 Yes

0 No

Question { 3348 }

In a star to star transformer can we use a common neutral for
both star connected primary and secondary

Answer

yes.this process is used to limit third harmonics produced in the line currents in transformer.

Is This Answer Correct ?

1 Yes

0 No

Question { Merchant Navy, 7057 }

to transmit 30kw of power at 30 km what is voltage required

Answer

this is the case of short transmission & it will have voltage less than 20 kv.even i marked 33 kv foolishly during exam.

Is This Answer Correct ?

6 Yes

5 No