How to calculate the average power factor in 3 phase
unbalanced system
Answers were Sorted based on User's Feedback
Answer / thakur
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 ? | 34 Yes | 9 No |
Answer / engr.abdurrahim
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
impedance=Z,
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.
R=R1+R2+R3
Z+Z1+Z2+Z3
(Where Z=R+jXL=Impedance)
cos@=R/Z
Hope my answer will satisfy you.
Best Regards,
Engr.Abdurrahim
shaikh337@rediffmail.com
Is This Answer Correct ? | 15 Yes | 7 No |
Answer / razi zainal abidin
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
regulator'
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 |
Answer / reddy
By using sequence components ... (+vesequence power - -ve
seq power)/VA
Is This Answer Correct ? | 0 Yes | 4 No |
before synchronizing an alternator,power factor is leading ,why?
Why transformer neutral earthing? What is advantages?
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
mostly the questions were from machines... d.c. machines, transformer, synchronous and induction all theory paper........ few from power system... but the level of paper was easy.....
HELLO SIR, IAM PREPARING HPCL EXAMS. SO PLS SEND MATERIAL OF HPCL ELECTRICAL ENG..TO VIJAY_8888@YMAIL.COM
what is the tolerance for the magnetic balance test conducted on the distribution transformer?
Why most of analog o/p devices having o/p range 4 to 20 mA and not 0 to 20 mA ?
what is surge voltage and surge current?
how to ctrl motor by use of ac or dc drive.plz explain evdintly
What is self exciting?
What is the purpose of taking Capacitance and Tan Delta Test in Transformer bushing?
what is the difference between an alternator and a synchronous motor