Abstract: Electrical equipment (14) is safeguarded from damage due to parallel arc faults by a circuit that provides several levels of protection. A semiconductor switch (18) and a current sensor (24) are placed in series with the electrical equipment (14). When the current to the equipment exceeds a first threshold for a predefined period of time, the semiconductor switch (18) is rendered non-conductive until the circuit is specifically reset. When the current to the equipment exceeds a greater second threshold, a pulsed signal alternately places the semiconductor switch (18) in conductive and non-conductive states so that the average current applied to the equipment (14) is within an acceptable level. The pulses are measured to determine whether a parallel arc fault has occurred. When the measured pulses (74) are within a predetermined range, a parallel arc fault is declared and the semiconductor switch (18) is rendered non-conductive.

Abstract: Electrical equipment (14) is safeguarded from damage due to parallel arc faults by a circuit that provides several levels of protection. A semiconductor switch (18) and a current sensor (24) are placed in series with the electrical equipment (14). When the current to the equipment exceeds a first threshold for a predefined period of time, the semiconductor switch (18) is rendered non-conductive until the circuit is specifically reset. When the current to the equipment exceeds a greater second threshold, a pulsed signal alternately places the semiconductor switch (18) in conductive and non-conductive states so that the average current applied to the equipment (14) is within an acceptable level. The pulses are measured to determine whether a parallel arc fault has occurred. When the measured pulses (74) are within a predetermined range, a parallel arc fault is declared and the semiconductor switch (18) is rendered non-conductive.

Abstract: A circuit assembly senses a state of a variable state device, wherein a data signal representative of the state is communicated via wireless telegraphy. A surface acoustic wave (SAW) device, having a plurality of interdigital transducers (IDTs) comprises a wave launching IDT and a state information IDT, wherein the plurality of IDTs are in acoustical communication and the state information IDT is in electrical communication with an antenna through the variable state device. An RF transceiver communicates a trigger signal to the SAW device, wherein the trigger signal causes a launching of a SAW wave from the wave launching IDT towards the state information IDT. The state information IDT generates a signal pulse in response thereto and communicates the pulse to the antenna through the variable state device.

Abstract: A control system for a washing machine having a transducer mounted on the exterior of the washing receptacle wall and operable to generate acoustic vibrations in the receptacle wall during fluid filling of the receptacle. A receiver detects sound waves within the receptacle generated by the wall vibrations and generates in fill signal indicative of the sound waves. Circuitry is provided for analyzing the fill signal and determining from the acoustic signature of the fill signal the occurrence of total immersion of articles in the fluid; and, the circuitry sends a signal which is operable to then shut off the fluid fill valve.