Answer / gurpreet sandhu

POWER factoris the cosine angle between Voltage and current
or it is the ratio of true power to apperant power

Answer / rajani

Power factor is the ratio of true power to apparant power
and it is the cosine of angle between voltage and current

P=V I *pf

if pf is poor ex: 0.17 to meet actual power load has to
draw more current(V constant),result in more losses

if pf is good ex: 0.95 to meet actual power load has to
draw less current(V constant),result in less losses

if cosign angle is 80degrees cos 90= 0.17 means pf =0.17
current vector is lagging 80degrees (i>>v) so load draws
more current so losses are high

if angle is 20 degrees cos 20 = 0.93 means pf =0.93 (good
pf) current is lagging only 20degrees, i value is less

so to decrease current drawn of the load we have to
maintain good pf

Answer / laxminarayana

Power factor should be high in order to get smooth
operation of the system.Low power factor means losses will
be more

Answer / das

it is the ratio of true power to apperent power. it has to
be ideally 1. if it is too low then cable over heating &
equipment overloading will occur. if it is greater than 1
then load will act as capacitor and starts feeding the
source. will cause nusence tripping

Answer / rishi

it is the ratio of true power to apperent power.it's value
should be less than 1.

Answer / hm

power factor: it is the percentage of electricity that is
converted into useful work(another form of energy) i.e
active power.

so we always require more active power. reactive power is
also drawn by machines which is required to establish and
sustain magnetic field.

ex:- for 60kw requirement, if machine operating at 0.6pf its
kva rating should be 100kva. if machine operating at 0.9pf
its kva rating will be 66.67kva only.

so pf should be maximum

Answer / parag

from economy point of view P.F should be high since;
KVA= KW/P.F
if P.F is high then KVA demand by the load will be less
which hels in saving of bill specially in industries where
they follow two part billing.

Answer / gajanan

pf is the cosine of angle between V & I ideal pf is unity bt
practically is not possible if t is low it means there s
losses occur.

Answer / aayush

PF= KW/ KVA
It should be maximum, as far as possible.

Answer / kbp prasad

PF = KW /KVA

PF value should be less than 1 and more than 0.9, then
losses will be resonable within the limit.

234 MVA Generator 3 phase Short circuit current Values required? Gen set Rating-234 MVA, Gen Voltage-18kv, PF;0.8, Xdv:23.5 %, Transformer Rating-18/380KV, 680MVA,Yndd1 two winding, Step up TR, ZT:35.50 %,X/R 4.33 Gen CB Position, CB open ,Disconnected open, Generator Running Voltage 18 Kv, Bi mistakes generator side earth switch Closed during that time short circuit current level in 3 Phase required, and how to test on site 234MVA Generator Short circuit current,

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