Rockwell Automation 1325L DC Motors, Frames C210ATZ - C440ATZ - Manual (Page 4)

4 DC Motors
Installation DC motors have characteristics which can cause serious or fatal
injury unless they are selected, installed, maintained and operated by
qualified personnel familiar with special requirements of DC
machines. Allen-Bradley DC motors are designed and built in
accordance with Safety Standard for Construction and Guide for
Selection, Installation and Use Of Electric Motors And Generators
published by the National Electrical Manufacturers Association
(NEMA), publication MG-2-1983 (ANSI C51.5). It is recommended
that this publication be referred to whenever you select or install any
motor.
The application of motors and other electrical equipment in
hazardous locations is restricted by the National Electric Code. Users
must observe these regulations and consult with local code inspection
and enforcement agencies to insure compliance.
Location
Locate the machine where the ambient temperature is not over 40
degrees C (104 degrees F) and where clean air has free access to
ventilating intake and outlet openings. Except for machines with a
suitable protective enclosure, the location should be clean and dry.
Important: Sufficient clearance must be provided on all inlet and outlet
openings to provide for unrestricted flow of air. Separately
ventilated motors with exhaust to ambient (pipe-in only)
must have at least 152.4 mm (6 in.) of clearance between
the opening and adjacent walls or floor.
Air Supply
Cooling air through a self-ventilated or forced-ventilated motor must
be clean and have relative humidity between 30 and 100% with no
free water in the air. Use of damp, cool outside air with high humidity
and free water may cause the motor to flash over. Use of excessively
dry air may cause excessive brush and commutator wear. Cooling air
temperature must not exceed the maximum ambient temperature
indicated on the motor nameplate (standard 40 degrees C/104 degrees
F). Cooling air temperature must not be lower than 0 degrees C (to
provide base speed and regulation within NEMA limits. Use of
outside air below 0 degrees C may cause excessive brush and
commutator wear due to the low humidity. Cooling air absolute
humidity must be at least 2 grains per cu. ft.
Important: Motors located in damp, moist environment must have
space heater or fields energized at 50% voltage to protect
against condensation when motor is not operating.
Separately ventilated motors must have the following volume of air to
adequately cool the motor unless the motor nameplate specifies a
different value.