Abstract: A pump installation used to maintain liquid level in a tank by pumping down liquid introduced into the tank with rotation of an impeller about a vertical axis features an air purging flow defined by axial openings through the pump impeller and an annular clearance space between the impeller drive and the pump housing cover, the space disposed above the impeller axial openings. A support sleeve surrounding the impeller drive and secured to the pump motor and tank top has openings at the bottom thereof which sets up a flushing liquid flow to eliminate solids forced up through the clearance space and into the sleeve interior.

Abstract: A revenue accuracy meter and a method are provided for measuring the amount and quality of power received by a power customer across electrical power lines. The revenue accuracy meter preferably has a variation determiner for determining undesired variations in an electrical signal representative of power received by the power customer during a plurality of predetermined time periods. A power usage measurer is coupled in electrical communication with the variation determiner for measuring the power usage of a customer responsive to an electrical signal representative of a customer load. The meter further has a communications interface coupled in electrical communication with the variation determiner and the power usage measurer for communication signals representative of the power variations and the power usage.

Abstract: The invention is for an optical communication apparatus for bidirectionally transmitting and receiving supervisory and audio signals. The apparatus includes a telephone line interface unit that receives electric audio and supervisory signals and converts them to optical signals. It is also includes means for receiving optical signals representing audio and supervisory signals. A data unit receives the optical audio and supervisory signals from the interface unit and converts them to electric audio and supervisory signals, and also includes means for receiving electric audio signals and supervisory signals and converting them to corresponding optical signals. An optical link connects the telephone line interface unit and data unit for bidirectional optical communication. A method of practicing the invention is also included.

Abstract: The method and apparatus disclosed relates to the electronic measurement of the electricity used by a load. The apparatus generates a rectified voltage signal proportional to the load voltage. A frequency modulated pulse train is generated in response to the load voltage signal, with the frequency of the pulses being proportional to the instantaneous amplitude of the rectified load voltage. A load current signal is generated that is proportional to the load current. A logic circuit gates the load current signal during each pulse of the frequency modulated pulse train to generate a signal representing the product of the instantaneous load voltage and the instantaneous load current. This signal from the logic means may be integrated over time to generate a signal representing the amount of electric energy used by the load. A method for practicing this invention is also disclosed.

Abstract: A load management control system and method which communicates load shedding information from a central station controller via existing telephone lines to a substation controller. The substation controller in turn controls the tap position selection of a load tap changing transformer to send encoded step voltage signals down a power distribution line to a load control receiver. The load control receiver decodes the encoded signal message and appropriately controls uniquely associated loads. The substation controller interrupts automatic operation of the voltage maintenance circuitry of the load tap changing transformer during transmission of a message. Control is returned to the automatic circuitry of the load tap changing transformer after the message is completed so as to make existence of the load management control system of the present invention transparent to existing equipment in the field.

Abstract: An upstream fluid chamber adapted for fluid flow in a given direction is interconnected to a downstream fluid chamber by a plurality of individually actuatable digital valve elements disposed in a plane substantially transverse to the given direction so that the pressure drop across each valve element is substantially the same. The valve elements are disposed so the fluid from the upstream chamber passing through the valve elements converges in the downstream chamber to dissipate the vena contracta. The areas of the valve elements are weighted so the smaller areas follow a geometric progression while the larger areas deviate from a geometric progression. Preferably, at least the two larger areas are the same size. The valve elements themselves each have an orifice, a plug, and means for maintaining the plug in one of two positions. The plug seals the orifice in the one position and lies outside of the fluid stream in the static fluid region in the other position.

Abstract: Individually actuatable digital valve elements in parallel interconnect a fluid source to a receiver. In the flow passage of each valve element, there is a converging-diverging nozzle that feeds into the receiver. A trim adjustment screw is movable along the axis of each nozzle to vary the effective cross-sectional area of such nozzle. The nozzle and screw are part of an insert that can be mounted in the valve body after individual calibration.

Abstract: An upstream fluid chamber adapted for fluid flow in a given direction is interconnected to a downstream fluid chamber by a plurality of individually actuatable digital valve elements disposed in a plane substantially transverse to the given direction so that the pressure drop across each valve element is substantially the same. The valve elements are disposed so the fluid from the upstream chamber passing through the valve elements converges in the downstream chamber to dissipate the vena contracta. The areas of the valve elements are weighted so the smaller areas follow a geometric progression while the larger areas deviate from a geometric progression. Preferably, at least the two larger areas are the same size. The valve elements themselves each have an orifice, a plug, and means for maintaining the plug in one of two positions. The plug seals the orifice in the one positon and lies outside of the fluid stream in the static fluid region in the other position.

Abstract: A plurality of individually actuatable, value weighted digital bistable valve elements in parallel interconnect a fluid source to a fluid receiver. A linear relationship is preferably maintained between the resultant fluid flow rate from the source to the receiver and the product of a flow rate determinative fluid parameter times the sum of the weighted values of the digital valve elements in the open state. The fluid parameter is sensed, the states of the digital valve elements are controlled, and a flow rate representative signal is derived from the states of the valve elements and the fluid parameter. If the fluid is liquid, the parameter is the square root of the pressure difference across the valve elements, in the absence of cavitating venturis, and is the square root of the difference between the upstream pressure and the vapor pressure of the liquid in the presence of cavitating venturis. If the fluid is gas, the parameter is the source pressure divided by the square root of the source temperature.