If motors are not immediately installed, they must be stored
in dry places, free of dust, vibrations, gases, corrosive smokes,
under constant temperature and in normal position free from
other objects.
In case the motors are stored for more than two years, the
bearings must be changed or the lubrication grease must be
totally replaced after cleaning.
Single phase motors when kept in stock for 2 years or more
must have their capacitors replaced (if any).
We recommend to turn the shaft (by hands) at least once a
month, and to measure the insulation resistance before
installing it, in cases of motors stored for more than 6 months
or when subject to high humidity areas.
If motor is fitted with space heaters, these should be
switched on.
Insulation Resistance Check
Insulation Resistance Check
Insulation Resistance Check
Insulation Resistance Check
Insulation Resistance Check
Measure the insulation resistance before operating the
motor and/or when there is any sign of humidity in the winding.
The resistance measured at 25°C (77
o
F) must be:
Ri > (20 x U) / (1000 + 2P) [Mohm] (measured with a
MEGGER at 500 V d.c.); where U = voltage (V); P = power
(kW).
If the insulation resistance is less than 2 megaohms, the
winding must be dried according to the following:
9
Warm it up inside an oven at a minimum temperature of
80°C (176
o
F) increasing 5°C (41
o
F) every hour until 105°C
(221
o
F), remaining under this temperature for at least one hour.
Check if the stator insulation resistance remains constant within
the accepted values. If not, stator must be reimpregnated.
STORAGE
