Bearing And Lubrication; Balancing, Transmission Elements; Commissioning - Siemens 1SE0 Operating And Maintenance Manual

Warning
While the measurement is being
taken and immediately afterwards,
some of the terminals carry
dangerous voltages and must not be
touched.
Measurement
The insulation resistance of the windings
to ground is measured with 500V DC. The
winding temperature should be 30ºC±15ºC.
Checking
Minimum insulation resistance value (at
40°C) as specified in IS: 4722 is Rm = kV
+ 1, where kV is the rated voltage of the
machine. Thus, for 415V rated voltage the
insulation resistance of the winding should
not be less than 1.42 MOhm.
If less the winding must be suitably dried as
per IS: 900
3.6

Bearing and lubrication

All motors, as a standard feature, are
provided with floating bearing at drive end
and fixed bearing at non-drive end.
62 series deep groove ball bearings
shielded on both the sides (ZZ) are
provided in motors upto 132 frame. Motors
up to and including frame 112 will have
bearing with "Normal" clearance whereas
bearings for 132 will have C3 clearance.
The grease used is lithium complex soap
based Exxon Mobil, UNIREX N3, NLGI
Class 3 or equivalent.
The double sealed (ZZ) bearings are pre-
lubricated for life. Under normal operating
condition, these offer a service life of
20,000 continuous working hours and
must be replaced after such period or 3
years whichever is earlier.
10
3.7

Balancing, transmission elements

A suitable device should always be used
for fitting and removing the transmission
elements (coupling halves, pulleys,
pinions).
As standard, the rotors are dynamically
balanced with the half key inserted.
When fitting the transmission element,
keep the type of balance in mind!
Balance with half key.
Warning
The usual measures should be taken
to guard transmission elements
from touch. If a motor is started
up without transmission element
attached, the key should be secured
to prevent it being thrown out.
3.8

Commissioning

NOTE: Where the torque is very uneven
(the drive of a reciprocating type
compressor, for example), the inevitable
result is a non-sinusoidal motor current,
whose harmonics can lead to excessive
system perturbation or excessive
electromagnetic interference.
In case of converter-fed motors, high-
frequency current or voltage harmonics
in the motor cables can give rise to
electromagnetic interference. This is why
the use of shielded cables is recommended.