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.

11KW Delta motor is taking about 44Amps in star and goes upto 70Amps in delta and trips OFF. The rated current is 26Amps. Application is for the blower. The motor takes ( no load without coupling impller ) only 2.5A and 5Amps in star & delta starter test.Need to know why its taking high current.

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