OMM-11-0211-page 7
B. Motors:
1.
DO NOT connect or operate a motor without reading the motor manufacturers instructions supplied with the
motor.
The basic principle of motor maintenance is:
KEEP THE MOTOR CLEAN AND DRY.
This requires periodic
inspections of the motor. The frequency of the inspections depends on the type of motor, the service and environment
it will be subjected to and the motor manufacturers instructions.
2. Cleaning:
Cleaning should be limited to exterior surfaces only.
Follow motor manufacturers cleaning instructions.
3. Lubrication:
Most small motors have sealed bearings that are permanently lubricated for the life of the motor. Some
larger motors have grease plugs that should be replaced with grease fittings to perform re-lubrication. These motors, or
any motor with grease fittings, should be lubricated in accordance with the motor manufacturers recommendations.
Lubrication frequency depends on the motor horsepower, speed and service.
BE SURE
you use compatible grease
and
DO NOT
over grease.
4. Location:
If the motor will be outside and subjected to the weather, it is recommended that a weather cover be
installed to keep rain and snow off of the motor. No motors are guaranteed to be “watertight”. Be careful to allow
enough openings between the motor and the motor cover to let the motor ”breath”. If the back end of the motor is cov-
ered, the cover should be no closer than 3” to the back of the motor for proper ventilation.
5. Wiring Connections:
All wiring connections should be made for the proper voltage and phase as shown on the motor
nameplate. Connections should follow the motor manufacturers recommendations as shown on the wiring schematic.
This wiring diagram will be located on the outside of the motor, inside of the motor conduit box or on the motor name-
plate.
Reversing some wires might be necessary to get the correct blower rotation.
6. Motors with Thermal Overload Protection:
If a motor is equipped with thermal overloads, the thermal overload must
be wired per the wiring schematic to be operable.
There are 3 types of thermal overloads:
a. Automatic:
These will automatically shut the motor down if the internal temperature exceeds the design limits.
b. Manual:
These motors will have a button on them. If the motor overheats, it will shut down. After you have
inspected the motor and eliminated the over heating problem, you will need to “reset” it by pushing the button.
Lock out the power BEFORE inspecting the motor.
c. Thermostats:
This type of thermal is a temperature sensing device
ONLY
. If the motor overheats, the thermo-
stats will open or close (depending on the type) and send a
“signal”
to the electrical box.
THEY WILL NOT
TURN THE MOTOR OFF.
These are pilot circuit devices that must be connected to the magnetic starter
circuit.
7. EXPLOSION PROOF Motors:
No motor is explosion proof. Explosion proof motors are designed so if there is an
explosion
WITHIN
the motor, the explosion will be
CONTAINED INSIDE
the motor and not allowed to get out to the
atmosphere. All explosion proof motors must be selected based on the atmosphere and/or the environment the motor
will be operating in. Explosion proof motors are designed, rated, and labeled for their operating conditions based on
Classes, Groups and “T” Codes.
The Class, Group and “T” code of an EXP motor MUST be selected based on the
atmosphere and/or environmental conditions the motor will be operating in. Consult the NEC (National Electric
Code) and the NFPA (National Fire Protection Association) for the proper EXP motor Class, Group and “T”
Code required for your specific application and location.
NOTICE:
a. All EXP motors have some type of thermal overload as required by UL (Underwriters Laboratories). Refer
to all of Section 6 above.
b. All EXP motors are required to have the UL (Underwriters Laboratories) and CSA (Canadian Standards
Association) listing numbers on the motor name plate or on a separate plate attached to the motor. The
Class, Group and “T” Code the motor is designed for must also be listed.
MAKE SURE YOU LOCK OUT THE POWER TO THE MOTOR BEFORE INSPECTING ANY MOTOR WITH
AUTOMATIC THERMALS, WHEN THE THERMALS COOL DOWN, THEY WILL ALLOW THE MOTOR TO
AUTOMATICALLY START UP AGAIN, UNLESS YOU HAVE LOCKED OUT THE POWER TO THE MOTOR.
DANGER
IF AN EXPLOSION PROOF MOTOR IS USED IN AN AREA CONTAINING VOLITILE LIQUIDS, GASES,
FUMES OR DUST FOR WHICH THE MOTOR WAS NOT DESIGNED TO OPERATE IN,
AN EXPLOSION AND/OR FIRE CAN OCCUR
DANGER
ALL WIRING CONNECTIONS, INSPECTION AND MAINTENANCE OF ANY MOTOR MUST BE PERFORMED BY
A LICENSED ELECTRICIAN IN ACCORDANCE WITH THE MOTOR MANUFACTURERS RECOMMENDATIONS,
ALL ELECTRICAL CODES AND OSHA REGULATIONS. FAILURE TO PROPERLY INSTALL, MAKE WIRING
CONNECTIONS, INSPECT OR PERFORM ANY MAINTENANCE TO A MOTOR CAN RESULT IN MOTOR
FAILURE, PROPERTY DAMAGE, EXPLOSION, ELECTRICAL SHOCK AND DEATH.
DANGER