The commonly available electric power supplied by an AC generator and is distributed in single or three phase forms. AC current changes its direction of flow (cycles).
A motor operating on AC current that flows in either direction (AC current). There are two general types: induction and synchronous.
The amount of steel (iron) in the stator and rotor of a motor. Usually the amount of active iron is increased or decreased by lengthening or shortening the rotor and stator (they are generally the same length).
The space between the rotation (rotor) and stationary (stator) members in an electric motor.
Used on motors with blowers to measure the difference in pressure across the filter to detect a clogged filter.
A device used with an air hood motor to detect the temperature of the exhausted air. When used in this manner an air temperature switch will detect blockage in the cooling air system or long-term motor overload.
The atmospheric altitude (height above sea level) at which the motor will be operating; NEMA standards call for an altitude not exceeding 3,300 feet (1,000 meters). As the altitude increases above 3,300 feet and the air density decreases, the air’s ability to cool the motor decreases. For higher altitudes, higher grades of insulation or motor derating are required. DC motors require special brushes for operation at high altitudes.
The temperature of the surrounding cooling medium, such as gas or liquid, which comes into contact with the heated parts of the motor. The cooling medium is usually the air surrounding the motor. The standard NEMA rating for ambient temperature is not to exceed 40°C.
An anti-friction bearing is a bearing utilizing rolling elements between the stationary and rotating assemblies.
The portion of the magnetic structure of a DC or universal motor which rotates.
Rated full load armature circuit current.
Armature inductance in milli-henries (saturated).
The current that flows in the armature winding of a DC tends to produce magnetic flux in addition to that produced by the field current. This effect, which reduces the torque capacity, is called armature reaction and can effect the commutation and the magnitude of the motor’s generated voltage.
Armature resistance is measured in ohms at 25°C (cold).
The force or loads that are applied to the motor shaft in a direction parallel to the axis of the shaft (such as from a fan or pump).