Abstract: Redundant heating systems include a plurality of heating circuits to heat a region. Heating circuits include a temperature sensor to sense a temperature of the region, a heating element, a temperature controller to provide power to the heating element based on the sensed temperature of the region, and a latching thermostat in series with the heating element. The latching thermostat consumes power supplied by the temperature controller to the heating element in response to a temperature of the latching thermostat reaching an open latch threshold temperature.

Abstract: Redundant heating systems include a plurality of heating circuits to heat a region. Heating circuits include a temperature sensor to sense a temperature of the region, a heating element, a temperature controller to provide power to the heating element based on the sensed temperature of the region, and a latching thermostat in series with the heating element. The latching thermostat consumes power supplied by the temperature controller to the heating element in response to a temperature of the latching thermostat reaching an open latch threshold temperature.

Abstract: A power control system includes a multi-phase power source, an ungrounded multi-phase load, a plurality of power switching circuits and a plurality of zero-crossing circuits. The multi-phase power source includes a plurality of phase power outputs. The plurality of power switching circuits are each connected to provide power from one of the plurality of phase power outputs to the ungrounded multiphase load. The plurality of zero-crossing circuits are connected to provide control signals to the plurality of power switching circuits. Each of the plurality of zero-crossing circuits are connected between one of the plurality of power phase outputs and an ungrounded reference.

Abstract: A power control system includes a multi-phase power source, an ungrounded multi-phase load, a plurality of power switching circuits and a plurality of zero-crossing circuits. The multi-phase power source includes a plurality of phase power outputs. The plurality of power switching circuits are each connected to provide power from one of the plurality of phase power outputs to the ungrounded multiphase load. The plurality of zero-crossing circuits are connected to provide control signals to the plurality of power switching circuits. Each of the plurality of zero-crossing circuits are connected between one of the plurality of power phase outputs and an ungrounded reference.

Abstract: A liquid level sensing system includes a vessel and an electrode. The vessel includes a vessel wall separating a vessel interior from a vessel exterior. The electrode is mounted to an exterior side of the vessel wall spanning a distance corresponding to a desired-level-determining range. The vessel wall is a dielectric gap between the electrode and the vessel interior. The electrode is configured to collect a charge corresponding to a liquid level. A method for determining a liquid level in a vessel includes collecting a charge on an electrode, sensing the collected charge on the electrode with a capacitance sensor through an electrical line, and determining a liquid level in a vessel based on the collected charge sensed by the capacitance sensor.

Abstract: A linear liquid level sensing system (10) comprises a vessel (20), an electrically conductive liquid (30) contained within the vessel (20), and a collector (40) spanning a vertical distance corresponding to the desired-level-determining range. An insulator (50) encases the collector (40) to define a dielectric gap between it and the fluid (30), with the insulated area in contact with the fluid (30) correlating with the fluid level. A single electrical line (60) connects the collector (40) to both a voltage-supplying source (70) and a charge-sensing device (80).

Abstract: A liquid level sensing system includes a vessel and an electrode. The vessel includes a vessel wall separating a vessel interior from a vessel exterior. The electrode is mounted to an exterior side of the vessel wall spanning a distance corresponding to a desired-level-determining range. The vessel wall is a dielectric gap between the electrode and the vessel interior. The electrode is configured to collect a charge corresponding to a liquid level. A method for determining a liquid level in a vessel includes collecting a charge on an electrode, sensing the collected charge on the electrode with a capacitance sensor through an electrical line, and determining a liquid level in a vessel based on the collected charge sensed by the capacitance sensor.

Abstract: A linear liquid level sensing system (10) comprises a vessel (20), an electrically conductive liquid (30) contained within the vessel (20), and a collector (40) spanning a vertical distance corresponding to the desired-level-determining range. An insulator (50) encases the collector (40) to define a dielectric gap between it and the fluid (30), with the insulated area in contact with the fluid (30) correlating with the fluid level. A single electrical line (60) connects the collector (40) to both a voltage-supplying source (70) and a charge-sensing device (80).