:: Home Page            
 Advertise your Business Here     
Browse  |   Placement Papers  |   Company  |   Code Snippets  |   Certifications  |   Visa Questions
Post Question  |   Post Answer  |   My Panel  |   Search  |   Articles  |   Topics  |   ERRORS new
   Refer this Site  Refer This Site to Your Friends  Site Map  Bookmark this Site  Set it as your HomePage  Contact Us     Login  |  Sign Up                      
Categories >> Engineering >> Electrical Engineering


 Civil Engineering interview questions  Civil Engineering Interview Questions (3120)
 Mechanical Engineering interview questions  Mechanical Engineering Interview Questions (3299)
 Electrical Engineering interview questions  Electrical Engineering Interview Questions (13431)
 Electronics Communications interview questions  Electronics Communications Interview Questions (2385)
 Chemical Engineering interview questions  Chemical Engineering Interview Questions (420)
 Aeronautical Engineering interview questions  Aeronautical Engineering Interview Questions (77)
 Bio Engineering interview questions  Bio Engineering Interview Questions (17)
 Metallurgy interview questions  Metallurgy Interview Questions (80)
 Industrial Engineering interview questions  Industrial Engineering Interview Questions (165)
 Instrumentation interview questions  Instrumentation Interview Questions (2398)
 Automobile Engineering interview questions  Automobile Engineering Interview Questions (107)
 Mechatronics Engineering interview questions  Mechatronics Engineering Interview Questions (38)
 Marine Engineering interview questions  Marine Engineering Interview Questions (45)
 Power Plant Engineering interview questions  Power Plant Engineering Interview Questions (79)
 Engineering AllOther interview questions  Engineering AllOther Interview Questions (1203)
How to calculate the average power factor in 3 phase 
unbalanced system
 Question Submitted By :: Electrical-Engineering
I also faced this Question!!     Answer Posted By  
# 1
Simply calculate total KWH and KVH of last 24 Hrs and
Divide into-Total KWH/Total KVH=Avg PF of last 24Hrs
Is This Answer Correct ?    31 Yes 6 No
# 2
Dear Deepak,

Power factor is the cosine factor of the voltage & current
phase difference. Its a short defination. But if you go
deeply, Power factor=cos@,its depend only on load, instead
of phasewise.if you connect same load in every phase it
will show same power factor value in each phase.Because
power factor is depended upon load resistance=R & its

cos@ = R/Z,

So if you are going to calcualte the power factor of all
phase, you have to calculate all resistance & impedance of
the load. Then you can calulate the avg. power factor.


(Where Z=R+jXL=Impedance)


Hope my answer will satisfy you.

Best Regards,
Is This Answer Correct ?    14 Yes 5 No
# 3
thanks, but cosider that R ph pf is 0.8,y-ph pf is 0.6,and
b ph pf is 0.7 what vlb the overall pf of three phase
unbalanced 3phase system .
Is This Answer Correct ?    6 Yes 5 No
# 4
Dear all,
This is not an answer, actually question.

In one factory, we are dificult to measure resistance,R and
impedance, Z.

What we have is only voltage supply (3phase, 420volt), and
total current flow during maximum usage using clampmeter
(including machinery, lamp, computers, etc...)

We also have info of main transformer step down because it
is in the factory area. Normally they stated value of KVA.

And some factory already install the 'capasitor bank

So, how we can calculate the CORRECT VALUE of capasitor
need to install?

I mean, which one is the correct KW, which one is the
correct KVA, and how to calculate existing power factor IF
the factory already have 'capasitor bank regulator'....can
we switsh of the regulator?
Is This Answer Correct ?    5 Yes 4 No
Razi Zainal Abidin
# 5
By using sequence components ... (+vesequence power - -ve
seq power)/VA
Is This Answer Correct ?    0 Yes 4 No

Other Electrical Engineering Interview Questions
  Question Asked @ Answers
I have a shop heater with a 1/3 hp capacitor start, induction motor driving the fan. Intermittently, the fan motor speeds up significantly for several seconds (15-60 sec) then slows to normal operating speed. The manufacturer suggested changing the capacitor which made no sense, but I did it to no avail. Could this possibly be caused by the centrifugal switch intermittently reconnecting the start winding?   1
in transformer star connection with neutral are shorted. is there is any effect.   1
What are the components of a substation? IOCL 3
How would you supply a single house hold load from a 3-phase supply coming out of a sub-station? Power-Grid 3
Hello friends i am facing one problem in lighting panel. Frequently neutral link near to MCCB is burning(firing. What may be the reason for this one. Please answer me.   5
why we are using the ac supply in domestic purpose why don't use dc supply SSIL 5
my UPS is 600VA with 0.6 p.f and i use it for my computer which has 450W power supply unit, a monitor of 633nW and speakers. Can any one explain this.. because the output of UPS should be 360W (<450W)   2
What is C check in a diesel generator and what are parts and what has to be done during the C check   4
Kindly give the brief explanations for checking 12.5 kvar 440V, 25 KVAR 440V, 12.5KVAR 690V, 25 KVAR 690V capacitors microfarad values. what is the microfarad values for the above four type of capacitors, and give the formula explanations briefly. I know F-50HZ, voltage, and capacitor.   1
how can we run the induction motor at 9000 rpm ,by keeping frequency constant??   2
Necessity of transformer earthing   1
how LVDT works?   2
For more Electrical Engineering Interview Questions Click Here 

Copyright Policy  |  Terms of Service  |  Articles  |  Site Map  |  RSS Site Map  |  Contact Us
Copyright 2013  All Rights Reserved.   ::