Glossary of Terms
Alternating Current (AC)
An electric current that reverses its direction many times a second at regular intervals, typically used in power supplies.
Alternating Current Motor (AC Motor)
An alternating-current (AC)motor in which torque is produced by the reaction between a varying magnetic field generated in the stator and the current induced in the coils of the rotor.
Air Performance Chart
A representation of the air output and electrical variations of products at various static pressures.
Part of the motor that is wound with magnet wire to create fields of magnetism to interact with the field ring.
Converts motor torque and rpm to an airflow perpendicular to the axis of rotation.
Brushless Motors (BLDC Motors)
Electronically commuted DC motor which does not have brushes. The controller provides pulses of current to the motor windings which control the speed and torque of the synchronous motor.
Brushless Resistor (BLDC Motor Speed Controller)
Controller adjusts the phase and amplitude of the DC current pulses to control the speed and torque of the motor. This control system is an alternative to the mechanical commutator (brushes) used in many conventional electric motors.
Term used in determining harness location within an assembly.
An attachment, connected to the armature of a motor or generator, through which electrical connection is made and which ensures that the current flows as direct current.
Flow of Air is perpendicular to Shaft and Parallel to Blades [vanes].
Method of measuring the imbalance with sensitive equipment while the fan blade or blower wheel rotates rapidly. It measures and displays the amount and location of imbalance in two separate pre-determined planes, described in distance times weight (ounce/inches for DCM), which then can be corrected to reduce the amount of imbalance and improve the vibration level when the component is introduced into the motorized assembly.
Electromagnetic Compatibility (EMC)
Interaction of electrical and electronic equipment with its electromagnetic environment, and with other equipment.
Electromagnetic Interface (EMI)
Disruption of operation of an electronic device when it is in the vicinity of an electromagnetic field (EM field) in the radio frequency (RF) spectrum that is caused by another electronic device.
Field Ring (Motors)
The outside magnetic ring that is either two pole or four pole and has opposite magnetic fields.
Hall Effect Sensors
Common method used to control BLDC Motor. Sensors are used to locate motor and control speed.
Variation of a part.
Permanent Magnet Motor (PM)
Uses permanent magnets in either the armature or stator.
Radio Frequency Interface (RFI)
(See Electromagnetic Interface). RFI is the older term.
Measured in ohms (Ω), amount of electrical potential divided by electrical charge = V (voltage) divided by A (amps).
A housing with increasing radial expansion, from “cut off” to outlet, used to collect and focus the output of the blower wheel (single or dual).
Part of the motor used to turn a fan blade or blower wheel.
Simplest form of imbalance, when an object’s center of gravity is on its axis of rotation, it will remain stationary. A fan blade or blower wheel is in static balance if it continues to be at rest at all angular positions of its axis. If this is does not hold true, the area with the heavier mass will rotate to the bottom of the static ways due to the force of gravity. The amount of imbalance can be reduced by adding balance clips opposite the location exhibiting the most mass (the section of the component at the bottom of the static ways). This reduces the amount of imbalance, moving the center of gravity closer to the axis of rotation, and improves vibration when the component is introduced into the motorized assembly.
Part of the motor that remains fixed with respect to the rotating parts.
Wound Field Motor (WF)
Although there are other types, the automotive market almost universally uses “series wound” motors, meaning voltage passes through one stator winding, then the armature, then the other stator winding aka “field wound.”