Abstract: An appliance having a drain pump with a motor adapted to be supplied with an alternating supply voltage. A controller is adapted to monitor a current value supplied to the motor and to control the frequency of the supply voltage among a plurality of predetermined frequencies when the drain pump is operated in a full drainage mode. A storage medium associated with the controller stores for each predetermined frequency a maximum current value, a minimum current value and an optimal current value. The controller may stores computer implemented instructions for (a) determining if the monitored current value is between the maximum current value and the minimum current value, (b) comparing the monitored current value with the optimal current value, and (c) adjusting the frequency of the alternating supply voltage among the plurality of predetermined frequencies to cause the monitored current to more closely match the optimal current value.

Abstract: A device and method for controlling a drainage pump of a washing machine. The drainage pump is powered by a synchronous motor that is connected to a mains voltage bus by a switch. During one or more stages of a washing program the switch is operated to apply in each half cycle of the mains voltage a delay time from the zero setting of the mains voltage to cause the motor to operate in a cut-wave mode.

Abstract: An appliance having a drain pump with a motor adapted to be supplied with an alternating supply voltage. The appliance also includes a controller adapted to monitor a current value supplied to the motor and to control the frequency of the supply voltage among a plurality of predetermined frequencies when the drain pump is operated in a full drainage mode. A storage medium associated with the controller stores for each predetermined frequency a maximum current value, a minimum current value and an optimal current value.

Abstract: A device and method for controlling a drainage pump of a washing machine. The drainage pump is powered by a synchronous motor that is connected to a mains voltage bus by a switch. During one or more stages of a washing program the switch is operated to apply in each half cycle of the mains voltage a delay time from the zero setting of the mains voltage to cause the motor to operate in a cut-wave mode.