Polarization Index (Pi); Infinite Setting - Circutor MI-15KVe Guia Del Usuario

8. Always remember to multiply the reading by the factor stated in the following
table, depending on selected test voltage, see fig. 4.
9. When key C x 10 is used, reading shall be carried out in range C and shall be
multiplied by 10, in addition to the factor corresponding to the test voltage.
10. When you press STOP KEY2, the insulation tester will start discharging the
potentials accumulated in the apparatus internal capacitances and in those of
the element under test as well. When this discharging process is over (up to 60
seconds after turn off) the HIGH-VOLTAGE LED, will turn off automatically.
The test leads may be disconnected. To finish measurement press ON/OFF0
switch.

Polarization index (PI)

For this type of tests, the instrument must be connected and apply high voltage to
the sample for 10 minutes. The polarization index is the ratio between the insula-
tion resistance value measured after 10 minutes and the value measured after 1
minute.

Infinite setting

The mechanical zero of galvanometer must be periodically checked. In order per-
form this checking, be sure that the insulation tester is off. The pointer should stay
on the right end of the scale just over the infinite mark on scale C. In other case,
the plastic screw at the bottom of the galvanometer acrylic cover shall be adjusted.
IP = R
10 min
R
1 min
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