Answer / t k shaw

Polarization Index Test ( PI ) – The PI test measures the
ability of the insulation to absorb voltage over a period
of time. This gives and indication of the overall
insulation quality of the individual pieces of insulation
in the transformer. This test is usually performed in
conjunction with the Megger Test.It is measured as ratio of
insulation resistance (IR)for 10 minutes to insulation
resistance for 1 minute.

Answer / sukhvinder

it is ratio of insulation resistance (IR)for 10 minutes to
insulation resistance for 1 minute.

it should be 1.5

Answer / gunasekaran

IR600sec/IR60sec
this value if it is less than 1 that system should be
replace or repaire if it 1.3 ok 1.5 is good 2 and above is
very good

Answer / r.s.nim

PI test measured the ability of the insulation to absorb
voltage over a period of time.This gives an indication of
the overall quality of insulation.

Answer / thota lokesh

Its ratio between insulation resistance(IR)i.e megger value
for 10min to insulation resistance for 1 min

it ranges from 5-7 for new motors & normally for motor to be
in good condition it should be >2.5 in case of PI value <2.5
over hauling should be conducted for motors and winding
should be thoroughly checked

Answer / rajendra

PI = Insulation resistane after 10min/Insulation resistane
after 1min.
or IR10/IR1 or IR+IL+IP/IR+IL
IR Conduction current
IL Surface leakage current
IP Porising current of water molecule presnt in the
Insulating matrials(usually zero after 10min)
Above 2 is adequate to run the machine below 2 needs
improvement??

Answer / s.ali

Polarisation or PI is the ratio of 10 minutes meggar value
to that of 1 minute.This value must not be less than 1, if
it is so then equipment like motor or transformer shuld not
be put into service for operation.

Answer / ricks

Its a capacity of insulation can withstand with volatge.
gives insulation healthiness,cleaness, moisture contains..
PI is taken as ratio of IR (10min)/IR(1 min).
SHOULD BE >2
1.5- HAZARDOUS
PI = 1+ (Ip/Is+Ir)

Answer / unknown

It is a test of the dielectric strength of the winding insulation.

Answer / bhushan

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