Abstract: An emulator which is able to operate on a standard single phase 120 VAC line, generates simulated three-phase alternating current in order to demonstrate the operation of a polyphase electricity meter. The emulator is also capable of demonstrating the operation of the polyphase electricity meter which has been incorrectly wired into the polyphase circuit, i.e., with incorrect or missing connections to the current transformers; or in which there are problems with the phasing of the polyphase circuit, i.e., incorrect phase differences between circuits or between the currents and voltages within any of the phases.

Abstract: A method and system is disclosed for indication and prevention of tampering with an electricity meter having control circuitry for automatic remote reading. The control circuitry, provided externally of the meter in a base or base extension, to which the meter is connected, is also used for tamper detection. Embodiments of the invention include use of optical sensing, voltage detection and proximity detection. Ambient light sensing may be performed to detect separation of the meter from the external receptacle. Reflected light to a reflective surface of the meter is sensed to determine if the meter is properly engaged. Presence of a meter connection plug element may be sensed either optically or by position responsive switch. Voltage of the utility supply and meter user output may be monitored to determine tampering.

Abstract: An optical sensor for monitoring position of a movable object comprising a LED and a phototransistor is provided with control circuitry, which is responsive to an output signal generated by the phototransistor for causing the LED to suspend radiation of light. When the light reflected from a reflective area of the object falls on the phototransistor, the control circuitry turns off the LED as soon as the output of the phototransistor goes below a threshold level signifying that the phototransistor has been turned on. When the light is absorbed by a non-reflective area of the object and the phototransistor is not turned on, the control circuitry turns off the LED after a predetermined time period, which is chosen to be slightly larger than the response time of the phototransistor.

Abstract: A dry (unpressurized) hydrant utilizes a hydrant pipe formed from PVC. One end engages a sliding swivel mount attached to a post with the other end of the pipe being free to swing and to be placed within a nearby body of water. The free end may include a strainer assembly, also formed of a PVC material. The strainer end may be placed at a predetermined depth within a body of water, such as a lake, pond or the like, by means of a second support located proximate the body of water. Alternatively, the strainer end of the hydrant pipe may be provided with a buoyant float to maintain the level of the strainer end of the hydrant pipe just below the water surface. In another embodiment, the strainer end of the hydrant pipe is provided with a rotating wheel assembly which enables the strainer end of the hydrant pipe to be rolled into position beneath the surface of the body of water. The dry hydrant is formed from inexpensive and lightweight materials and can be stored dry when not in use.

Abstract: A self-actuating throttle valve for use with fluid measurement apparatus such as a water meter. The valve includes a cylindrical body disposed within the outlet of the fluid measuring apparatus, fluid bypass openings formed in the body to enable fluid to flow through the body, and a piston disposed within the body. The piston is biased by a spring in a first position whereby the fluid may flow around the piston and body and through the bypass openings when the rate of fluid flow is below a predetermined amount. When the rate of fluid flow is above a predetermined amount, pressure from the fluid causes the piston to move to a second position whereby the piston covers the bypass openings by a predetermined amount to substantially reduce fluid flow. The throttle valve prevents damage to the fluid measurement apparatus when high fluid flow rates are encountered. The valve has particular application in the area of fire service water metering devices which include both a high flow rate measurement device (e.g.

Abstract: A two wire/three wire utility data communications system for remotely reading utility meter registers. In the two wire version, a hand-held reading unit is inductively coupled over two wires via a port located remotely from a meter register. Alternatively, a meter interface unit (MIU) may be connected directly to the register via three wires. Each register includes one or more wheel position encoders. An AC interrogation signal is applied by the reading unit to encoder circuitry at the meter which powers the circuitry and causes the position of each encoder wheel to be read. In the two wire mode, register display information (e.g. the current meter reading) is transmitted back to the reading unit by varying the load (impedance) presented by the register side of the circuit. This causes a corresponding variation of the amount of current drawn from the reading unit. The current-modulated signal is decoded by the reading unit and converted into a register reading.

Abstract: An improved drive shaft for a positive displacement type water meter includes a flexible spring arm formed on one end of the shaft for engaging the drive spindle of a nutating disk measuring element disposed within a water meter. The other end of the drive shaft is connected to a magnetic drive which, in turn, is magnetically coupled to a conventional mechanical register. Under normal conditions, the nutating disk measuring element and drive spindle oscillate in the water meter at a rate proportional to water meter flow. The drive spindle engages the spring arm of the drive shaft causing the drive shaft and magnet to rotate. The magnet is coupled through the water meter casing to a second magnet in the register. Rotation of the second magnet is used to drive the mechanical register to register water consumption. In the event the first magnet within the meter casing becomes frozen to the casing because of external freezing conditions, the drive spindle will snap past the flexible spring arm.

Abstract: A two wire/three wire utility data communications system for remotely reading utility meter registers. In the two wire version, a hand-held reading unit is inductively coupled over two wires via a port located remotely from a meter register. Alternatively, a meter interface unit (MIU) may be connected directly to the register via three wires. Each register includes one or more wheel position encoders. An AC interrogation signal is applied by the reading unit to encoder circuitry at the meter which powers the circuitry and causes the position of each encoder wheel to be read. In the two wire mode, register display information (e.g. the current meter reading) is transmitted back to the reading unit by varying the load (impedance) presented by the register side of the circuit. This causes a corresponding variation of the amount of current drawn from the reading unit. The current-modulated signal is decoded by the reading unit and converted into a register reading.

Abstract: A method and system for accurate remote reading of an electricity meter including an optical detection arrangement, including a light emitter and sensor, have positioned in the light path therebetween a cutout portion of the meter shaft. Rotation of the shaft affects the amount of light passed to the sensor. Registration errors which may occur in a linear transition operating range are avoided by provision of detector threshold hysteresis. A microprocessor sets timing pulses for emitter energization, establishes a detection period of uniform length of time for each energizing pulse and produces, during each detection period, a digital signal having a logic level indicative of the presence or absence of light transmitted to said sensor, whereby a correlation between light transitions and power usage can be made.

Abstract: A telephone dial-inbound data acquisition system with demand reading capability. The system has particular application for remotely reading utility meters. A remote data unit (RDU) dials up a host computer on a periodic basis. The RDU is assigned a callback start time by the host computer. The RDU calculates an actual callback time based on the callback start time and a randomly generated time delay. The RDU dials up the host computer via a modem when the local time, as shown by an on-board real-time clock at the RDU, equals the calculated actual callback time. Meter reading data is then transferred to the host computer. The RDU also contains circuitry for detecting a polling signal generated by the host computer. Upon detection of this polling signal, the RDU immediately dials back the host computer and transfers utility meter reading data to the host computer. The RDU will also immediately dial back the host computer if an alarm condition occurs, e.g. tampering or a low battery condition.

Abstract: A microprocessor based time-of-use electricity meter register uses an external real time clock powered by a backup battery during a power outage to measure real time elapsed during the outage. Upon detection of a power outage, line power and real time data are transferred by the microprocessor to an external, non-volatile memory, the external real time clock is energized by the backup battery and the clock reset to accumulate elapsed real time (days, hours, minutes, seconds) during the duration of the outage. Upon resumption of line power, the elapsed real time accumulated by the clock and the content of the non-volatile memory are transferred to the microprocessor, the backup battery is disconnected from the external real time clock and the real time previously stored in the nonvolatile memory is updated by the elapsed real time so that no customer billing data are lost during the outage.

Abstract: The present invention provides compensation for temperature in a transducer by connecting the adjustment resistors to the transducer itself to provide a correct transducer output. A number of switches are used to couple the adjustment resistors to the transducer circuit. An individual resistor may be coupled in parallel or in series with a transducer resistance. The control input for the switches are each coupled to a separate bit output of a multiple bit memory. The memory is programmed to control the duty cycle of the switches when addressed.

Abstract: A two wire/three wire utility data communications system for remotely reading utility meter registers. In the two wire version, a hand-held reading unit is inductively coupled over two wires via a port located remotely from a meter register. Alternatively, a meter interface unit (MIU) may be connected directly to the register via three wires. Each register includes one or more wheel position encoders. An AC interrogation signal is applied by the reading unit to encoder circuitry at the meter which powers the circuitry and causes the position of each encoder wheel to be read. In the two wire mode, register display information (e.g. the current meter reading) is transmitted back to the reading unit by varying the load (impedance) presented by the register side of the circuit. This causes a corresponding variation of the amount of current drawn from the reading unit. The current-modulated signal is decoded by the reading unit and converted into a register reading.

Abstract: The present invention is a method by which a dial inbound MIU is able to provide for connection with a central station computer without the need for any specialized telephone equipment at the telephone company's central office. If the customer's phone has been called, the invention detects whether the customer has answered. It then waits until the customer hangs up, and when the customer hangs up it siezes the line and waits for a modem tone indicative of the presence of the central station computer waiting to establish communication. If that modem tone is present, the MIU will connect to the central computer and permit communication to take place before releasing the phone line.

Abstract: A sealed utility meter having internal automatic disconnection. The meter contains a battery source of power for energizing the circuitry and is used in its operating environment in a horizontal position. In order to minimize battery drain prior to operation the meter is provided with a tilt switch mounted at a substantially 45.degree. angle to horizontal to energize the meter when it is in its operating position and deenergize the meter when it is removed from that position. The meter is packed in a container with packaging material which determines the packed position of the meter and the packing carton is provided with indicia to indicate the proper shipping and storage orientation of the carton. When the meter is thus packed and the carton thus oriented the circuitry is deenergized.

Abstract: A Coriolis-type mass flow meter for use in sanitary applications. A pair of sensing tubes have their ends rigidly mounted within bores formed within identical inlet and outlet fixtures. The ends of the tubes fit snugly within the bores and are ends brought out flush with the ends of the bores. The flush ends of the tubes are secured to the bores by means of welding. An annular flange is formed about the flush tube ends of the inlet and outlet fixtures to allow easy assembly and removal of the mass flow meter from its associated fluid flow pipeline or conduit. The inlet and outlet fixtures and tubes preferably are formed from a non-reactive, weldable material such as stainless steel. The mounting arrangement of the tubes within the bores of the inlet and outlet fixtures makes it easy to secure the tube ends to the fixtures by means of welding in a readily accessible location.

Abstract: An electromechanical sensor is provided which comprises: first semiconductor wafer including a first stop surface residing in a first shallow recessed region of the first wafer; a second semiconductor wafer; wherein the first and second semiconductor wafers are laminated together such that the first recessed region of the first wafer and the second wafer define a first chamber in which the first stop surface and the second wafer are disposed close enough together such that the first stop surface restrains the second wafer from deflecting beyond the first stop surface; and an apparatus for measuring deflection of the second wafer.