Dc motor field heating – Rockwell Automation 1325L DC Motors, Frames C210ATZ - C440ATZ User Manual
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DC Motors
In addition to observing the above precaution, all precautions
(Attentions) mentioned in this document should be observed.
•
The armature should rotate freely and be clear of any
obstructions.
•
The brushes should move easily in their holders and should make
proper contact on the commutator.
•
The interior of the motor should be clean and dry.
•
Connections must be tight.
•
The driven machine should be unloaded, if possible.
When starting, small sparks may appear on the commutator due to
particles of dirt. Other than this. there should be little, if any, sparking
at the brushes.
Important: Machines designed for cooling by a separate source of
forced ventilation must not be operated without the air
supply. Be sure blower is running in proper direction.
While operating the motor, observe the performance. It should run
smoothly with little noise. The bearings should not overheat and
should reach a leveling off temperature. Any undue noise,
overheating, sparking or erratic performance should be investigated
and necessary corrective action taken immediately to prevent serious
damage. Before attempting any repairs, please contact your Allen-
Bradley Sales Office.
All motors are lubricated before shipment and will operate for a long
period before regreasing is required. The period will vary depending
on environmental and service conditions. Refer to
DC Motor Field Heating
!
ATTENTION: Surface temperature of the motor enclosure
may reach temperatures which can cause discomfort or
injury to personnel coming into contact with hot surfaces.
The user must apply appropriate guards and/or shields to
protect against accidental contact. Failure to observe this
precaution may result in personal injury.
!
ATTENTION: To guard against motor damage caused by
inadequate ventilation, assure that motors designed for
forced ventilation as standard have cooling air when fields
are excited at rated voltage. Installations having the air
supply interrupted when the motor is not operating must
have field disconnected or field voltage reduced to 67%,
rated by means of field economizing resistor and relay. The
motor insulation life can be significantly reduced if the
above precaution is not followed.