Maintenance and Troubleshooting of Electric Motors

CHAPTER 1 - Motor Maintenance

Scheduled Routine Care
| Introduction | Dirt and Corrosion | Lubrication | Heat, Noise and Vibration | Winding Insulation |
Brushes and Commutators (DC Motors) | Brushes and Collector Rings (Synchronous Motors) |

Bearing Lubrication
| Introduction | Oiling Sleeve Bearings | Greasing Ball and Roller Bearings |

Heat, Noise and Vibration
| Heat | Noise and Vibration |

| Care of Windings and Insulation | Testing Windings | Cleaning and Drying Windings |

Brush and Commutator Care

CHAPTER 2 - Troubleshooting AC Motors

Problem A Motor won't start or motor accelerates too slowly
Problem B Motor runs noisy
Problem C Motor overheats
Problem D Motor bearings run hot or noisy

CHAPTER 3 - Troubleshooting DC Motors

Problem E Motor won't start
Problem F Motor starts but stops and reverses direction
Problem G Motor runs hot but overload protective device trips too often
Problem H Motor overheats
Problem I Motor runs too slowly
Problem J Motor runs too fast
Problem K Motor runs noisy
Problem L Motor bearings run hot or noisy
Problem M Brushes sparking excessively; may be accompanied by brush chatter and/or excessive wear and chipping

Note: This material is not intended to provide operational instructions.
Appropriate Reliance Industrial Company instruction manuals
and precautions should be studied prior to installation, operation, or
maintenance of equipment.