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MN605
4. If the motor must be mounted to a plate with the driven equipment such as pump, compressor etc., it may
not be possible to lift the motor alone. For this case, the assembly should be lifted by a sling around the
mounting base. The entire assembly can be lifted as an assembly for installation.
Do not lift the assembly using the motor lugs or eye bolts provided. Lugs or eye bolts are designed to lift
motor only. If the load is unbalanced (as with couplings or additional attachments) additional slings or other
means must be used to prevent tipping. In any event, the load must be secure before lifting.
Storage
Storage requirements for motors and generators that will not be placed in service for at least six months from
date of shipment. To avoid condensation inside the motor, do not unpack until the motor has reached room
temperature. (Room temperature is the temperature of the room in which it will be installed). The packing provides
insulation from temperature changes during transportation.
Improper motor storage will result in seriously reduced reliability and failure. An electric motor that does not
experience regular usage while being exposed to normally humid atmospheric conditions is likely to develop rust
or rust particles on surrounding surfaces to contaminate the bearings. The electrical insulation may absorb an
excessive amount of moisture leading to the motor winding failure.
A wooden crate “shell” should be constructed to secure the motor during storage. This is similar to an export box
but the sides & top must be secured to the wooden base with lag bolts (not nailed as export boxes are) to allow
opening and reclosing many times without damage to the “shell”.
Minimum resistance of motor winding insulation is 5 Meg ohms or the calculated minimum, which ever is greater.
Minimum resistance is calculated as follows: Rm = kV + 1
where: (Rm is minimum resistance to ground in Meg−Ohms and
kV is rated nameplate voltage defined as Kilo−Volts.)
Example: For a 480VAC rated motor Rm =1.48 meg−ohms (use 5 MΩ).
For a 4160VAC rated motor Rm = 5.16 meg−ohms.
Preparation for Storage
1. Some motors have a shipping brace attached to the shaft to prevent damage during transportation. The
shipping brace, if provided, must be removed and stored for future use. The brace must be reinstalled to hold
the shaft firmly in place against the bearing before the motor is moved.
2. Store in a clean, dry, protected warehouse where control is maintained as follows:
a. Shock or vibration must not exceed 2 mils maximum at 60 hertz, to prevent the bearings from
brinelling. If shock or vibration exceeds this limit vibration isolation pads must be used.
b. Storage temperatures of 10°C (50°F) to 49°C (120°F) must be maintained.
c. Relative humidity must not exceed 60%.
d. Motor space heaters (when present) are to be connected and energized whenever there is a possibility
that the storage ambient conditions will reach the dew point. Space heaters are optional.
Note: Remove motor from containers when heaters are energized, reprotect if necessary.
3. Measure and record the resistance of the winding insulation (dielectric withstand) every 30 days of storage.
a. If motor insulation resistance decreases below the minimum resistance, contact your
Baldor District office.
b. Place new desiccant inside the vapor bag and re−seal by taping it closed.
c. If a zipper−closing type bag is used instead of the heat−sealed type bag, zip the bag closed instead of
taping it. Be sure to place new desiccant inside bag after each monthly inspection.
d. Place the shell over the motor and secure with lag bolts.
4. Where motors are mounted to machinery, the mounting must be such that the drains and breathers are fully
operable and are at the lowest point of the motor. Vertical motors must be stored in the vertical position.
Storage environment must be maintained as stated in step 2.
5. Motors with anti−friction bearings are to be greased at the time of going into extended storage with periodic
service as follows:
a. Motors marked “Do Not Lubricate” on the nameplate do not need to be greased before or during storage.
b. Ball and roller bearing (anti−friction) motor shafts are to be rotated manually every 3 months and greased
every 6 months in accordance with the Maintenance section of this manual.
c. Sleeve bearing (oil lube) motors are drained of oil prior to shipment. The oil reservoirs must be refilled to
the indicated level with the specified lubricant, (see Maintenance). The shaft should be rotated monthly
by hand at least 10 to 15 revolutions to distribute oil to bearing surfaces.
d. “Provisions for oil mist lubrication” – These motors are packed with grease. Storage procedures are the
same as paragraph 5b.
e. “Oil Mist Lubricated” – These bearings are protected for temporary storage by a corrosion inhibitor.
If stored for greater than 3 months or outdoor storage is anticipated, connected to the oil mist system
while in storage. If this is not possible, add the amount of grease indicated under “Standard Condition”
in Section 3, then rotate the shaft 15 times by hand.
6. All breather drains are to be fully operable while in storage (drain plugs removed). The motors must be stored
so that the drain is at the lowest point. All breathers and automatic “T” drains must be operable to allow
breathing and draining at points other than through the bearings around the shaft.
Vertical motors should be stored in a safe stable vertical position.
7. Coat all external machined surfaces with a rust preventing material.
An acceptable product for this purpose is Exxon Rust Ban # 392.
8. Carbon brushes should be lifted and held in place in the holders, above the commutator, by the brush
holder fingers. The commutator should be wrapped with a suitable material such as cardboard paper as a
mechanical protection against damage.
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