Page 209

NORA Oilheat Technicians Manual

Chapter 10 Motors Chapter 10—Motors 10-3 Introduction Electric motors run the fuel unit, run the fan, providing combustion air to the fire, run the circulating pumps in a hot water system, and power the blowers in forced warm air and air conditioning systems. In addition, low voltage motors open and close zone valves and damper motors. Motor components Residential and commercial oilburner motors are generally AC motors. DC motors are sometimes used in some specialty applications, such as power washers and road maintenance equipment. Most motors use AC split-phase induction motors equipped with two sets of windings. This type generally has low to moderate starting torque with high amp draw on start-up. There are basic components of a motor: Base: the device used to support the motor. Rotor: The permanent magnets or windings attached to the motor shaft that follow the rotating magnetic field created by the electromagnets in the stator and cause the rotation of the motor shaft. Stator: The stator contains stationary electromagnets and windings that create the field that causes the motor to turn. The start and run windings are wound around the stator. When electricity flows through these windings, it creates the magnetic field. Start windings: Electric current flowing in these windings provides the extra power needed to start the rotor turning and are turned off when the motor is up to full Figure 10-1: Cutaway of burner motor Motor Windings Self-Aligning Sleeve Bearings Rotor Stator Centrifugal Switch Manual Reset Thermal Overload Chapter 10 Motors Twin Oiling Ports (If Applicable)


NORA Oilheat Technicians Manual
To see the actual publication please follow the link above