Abstract: A system for defogging doors to a display case is described and includes an electric motor and an air moving device. The air moving device is operatively coupled to the electric motor and positioned to provide an output proximate to at least one door of the display case. The motor is configured to operate at a first speed under standard closed door conditions, at a second speed when the door of the display case is open, and at a third speed for a predetermined length of time after the door is moved from an open position to a closed position.

Abstract: A method for determining a direction of rotation for an electronically commutated motor (ECM) is described. The motor is configured to rotate a blower and the method comprises rotating the blower using the ECM and determining if the resulting blower rotation is indicative of the desired direction of rotation for the blower.

Abstract: A motor control system for heating, ventilation, and air conditioning (HVAC) applications is described. The motor control system includes a thermostat and an electronically commutated motor (ECM) coupled to the thermostat. The ECM is configured to retrofit an existing non-ECM electric motor included in an HVAC application and to operate in one of a plurality of HVAC modes. The HVAC modes include at least one of a heating mode, a cooling mode, and a continuous fan mode. The HVAC mode is determined based at least partially on outputs provided by the thermostat.

Abstract: A method for determining a direction of rotation for an electronically commutated motor (ECM) is described. The motor is configured to rotate a blower and the method comprises rotating the blower using the ECM and determining if the resulting blower rotation is indicative of the desired direction of rotation for the blower.

Abstract: An electric motor is described that includes a mid-shield, a chassis, and a motor control unit configured to be mounted to the chassis. The chassis includes a plurality of clinches formed proximate a first end of the chassis and configured to provide axial positioning of the mid-shield with respect to the chassis.

Abstract: A method for applying power to an electronically commutated motor (ECM) is described. The method includes connecting an AC voltage source to an input of a rectification circuit, connecting a DC voltage source to an output of the rectification circuit, and electrically connecting the DC voltage source and rectification circuit output to operational components of the ECM. The DC voltage source is capable of providing a voltage equal to or greater than a rectified voltage originating from the AC voltage source, and the DC voltage source is connected in parallel with the output of the rectification circuit.

Abstract: A method for controlling a motor is described. The method includes configuring a current sensor to sense a current supplied to the motor from at least one of a plurality of power lines and to generate at least one current signal indicative of the sensed current. The method also includes coupling a processing device to the current sensor such that the processing device receives the current signal. The method also includes configuring the processing device to determine which of the plurality of power lines is active based at least partially on the current signal and generate a motor speed control signal that directs the motor to operate at the motor speed that corresponds to the active power line.

Abstract: A method for reducing leakage currents in an electric machine is described. The method includes positioning a plurality of leakage current shields between windings and teeth of a stator, and coupling at least one of the plurality of leakage current shields to a reference point, wherein an electric potential at the reference point is not earth ground.