7. Service
7.1 Maintenance
In order to ensure the safe and reliable operation of the
motor, regular inspection and maintenance must be carried out, and
hidden risks must be identified to prevent failures. Perform the
inspection and maintenance of the motor according to the principles
below.
7.1.1 Routine inspections during operation
• In case of any sudden increase in noise or vibration of
the motor, the motor must be stopped immediately.
• In case of continuous operation, perform periodic in-
spections at least once a day.
• The motor must be kept clean to prevent oil, water or
other dirt entering the motor.
• Make sure that the motor is well-ventilated, the air in-
lets and outlets are not obstructed and meshes are
cleaned frequently.
• The operation of the motor must be frequently moni-
tored. If you detect any abnormalities, stop the motor
immediately for inspection to prevent failures.
7.1.2 Shutdown inspection
If any of the following abnormal conditions occur, the motor must be
stopped immediately for inspection:
• heavy vibration
• damage to the driven machine
• bearing damage or overheat
• bearing misalignment and axial vibration
• sudden drop in speed
• friction between stator and rotor, enclosure overheat
• motor or starting device emits fumes
• personal injury.
7.1.3 Periodic inspection
Depending on the operating conditions, the motor must be
inspected periodically.
• Check if the fixing bolts are loose or corroded, affecting the
fixing performance.
• Check that the electrical connection is fastened and there is no
rust affecting the contact performance.
• Check that the earthing is fastened and there is no rust affecting
the earthing performance.
• Check if the shaft seal is worn. If yes, replace it. Contact your
local Grundfos company for any detailed specifications.
• Check that the coupling is firmly fixed and ensure concentricity.
• Check if there is liquid inside the motor affecting the motor
performance. If yes, discharge it.
• Check the bearings and replace them immediately if worn.
• Check the paint on the motor. If needed, repaint the motor to
prevent excessive corrosion.
7.1.4 Motor maintenance
Motors must be maintained periodically and faults must be
eliminated immediately. In general, a minor maintenance
per month and a major maintenance per year is needed.
7.1.4.1 Minor maintenance
• Clean the dust on the surface of the motor.
• Measure the insulation resistance of the motor.
• Fasten the fixing bolts, earth studs and other connecting bolts.
• Clean the starting device and the insulating terminals.
• Clean the mesh on the fan cover to ensure that the air inlet and
outlet are not obstructed.
7.1.4.2 Major maintenance
• Perform all the tasks included in minor maintenance.
• Clean the inside of the motor to keep the stator winding clean,
free of grease and with no exposed copper.
• Replace the bearings if damaged. Under normal operating
conditions, we recommend replacing the bearings once a year
(runtime is approximately 8000 hours per year).
• If there is no need to replace the bearings, clean the bearings
and change the grease.
• Clean or replace other parts of the motor.
7.2 Lubrication
The correct lubrication directly affects the lifetime of the bearings
and motors, so it is important to grease the bearings correctly and
regularly.
For smaller motors, bearings of ZZ types are usually permanently
greased. These pre-greased bearings do not need to be regreased.
Larger motors (H180 and above) and motors with specific
requirements are equipped with a greasing device. These motors
are factory greased, but it is necessary to change the lubrication
at regular intervals. The exact interval depends on the size and
usage of the motor.
If the machine is equipped with a regreasing plate, follow
the given values.
TM1040218
Dust seals, lubricator fittings and regreasing plate on MMG-W
Pos. Description
1 Dust seals and lubricator fittings
2 Regreasing plate
REGREASING
Grease Interval:
Grease amount:
Grease type: Polyrex EM-2
XXXX
XX
hours
gr.
TM1040217
Regreasing plate
8
English (GB)
