It should be near to one(less than one) . but not to one.
For stability static device has come which control the
capacitor bank automatically. So there is no problem of
stability . If anyone are going for the small industry , he
should try to maintain it near to .95. .80 is not so
effective power factor now a days. It can be acceptable for
home application not for the industrial purpose.
In Industrial sector there are more inductive loads.The
inductive loads draws more load current.So maximum will be
the power factor less will be the load currnt.So power
factor should be maintained 0.97 to 0.99
We maintain 0.8 and above since we are penalised by KEB for
low pf. we generally maintain close to 0.9 by use of power
capacitors. Too high i.e. above .95 is too costly to
install and also the problem is that if power factor is
close to 1 then there are chances of high voltage affects
motors and we suffer more motor burning at our plant.
In industries, mostly the loads are inductive type. So the
PF is low near about 0.8 lagging. Due to that the load
current is maximum.We can improve the PF by using Capacitor
bank in industrial substation. So that we can improve Pf
upto 0.99. For that proper design of capacitor bank is