Abstract: An electronic energy meter which receives a measurement request, and responsive to the measurement request and data stored in data tables in a memory, performs a function and generates output information. The output information is outputted in accordance with a predetermined priority scheme. Each different type of measurement request has a different output priority. An electronic energy meter that permits the addition of new measurements or testing capabilities without requiring factory modifications to effect such functionality changes is also disclosed.

Abstract: A system for monitoring power quality events of electrical energy provided to an energy meter via a service type comprises a memory for storing reference information reflective of different service types, a digital signal processor for measuring characteristics of the electrical energy, and a microcontroller for retrieving the reference information from the memory and comparing the measured characteristics to the reference information for the service type to determine the occurrence of power quality events. For each power quality event, at least one of a start time, a stop time, a duration, a measured phase, a magnitude of a measured quantity, and a predisturbance value, and a cumulative total of the power quality events is recorded.

Abstract: An apparatus for electronically communicating metered electrical power is disclosed. A first processor receives voltage and current signals and determines electrical power. The first processor generates an power signal representative of the electrical power determination. A second processor, connected to said first processor, receives the power signal and generates an output signal representative of electrical power information. A output device is connected to receive the output signal to output the electrical power information. The first processor determines units of electrical power from the voltage and current signals and to generates an power signal representative of the determination of such units and the rate at which the units are determined. The output devices may be one of a display, optical port and an option connector.

Abstract: An apparatus for metering electrical power includes a first processor which receives analog voltage and current signals and converts the analog voltage and current signals to respective digital voltage and current signals, a second processor which receives the energy signal and converts an energy signal into energy usage data, and a non-volatile memory coupled to the second processor for storing calibration constants and energy formula associated with a plurality of meter forms, such that some of the energy formula and calibration constants are downloaded from the non-volatile memory to the second processor. The first and second processors cooperate to determine the energy usage data based on the energy formula and calibration constants downloaded to the second processor, and the apparatus measures at least one of real power, reactive power, and apparent power based on energy formula and calibration constants associated with the plurality of meter forms.

Abstract: A method and apparatus to detect off-hook and intrusion conditions on a telephone line. A voltage to frequency converter is used to convert the voltage measured between the TIP and RING terminals of a telephone line to a frequency. The voltage is continuously monitored, once during each sample period. The measured frequency is compared to predetermined threshold values to determine the state of the telephone line. The predetermined threshold values are updated in each sample period.

Abstract: Methods and apparatus for supplying power for use in metering electrical energy over a wide range of voltages with a single meter are disclosed. The wide ranging meter includes a processing unit for processing divided input voltage and a current component in order to determine electrical energy metering values. The processing unit is operable in response to supply voltages. A power supply, connected to receive the undivided voltage component, generates the supply voltages over the wide dynamic range. It is especially preferred for the power supply to include a transformer having first, second and third windings, wherein the undivided voltage component is provided to the first winding and wherein the second winding defines the output of the power supply. A switching member is connected to the first winding for permitting and preventing the flow of current in response to a control signal. A control member generates the control signal in response to the output of the power supply.

Abstract: A system for monitoring near-instantaneous system parameters of electrical energy having at least one phase provided to an energy meter via a service type comprises a memory for storing reference information reflective of different service types, a digital signal processor for measuring characteristics of the electrical energy, and a microcontroller for retrieving the reference information from the memory and determining the near-instantaneous system parameters responsive to the reference information for the service type and the measured characteristics. The characteristics are derived from phase voltage and phase current, and are measured for a predetermined amount of time, such as a number of line cycles.

Abstract: A communications module that permits remote meter reading of a utility meter via a wireless modem that communicates using data packet networks along a communications system, such as ARDIS. The communications module is a microprocessor-based transmitter/receiver which receives data collection requests from a system server, initiates data collection from a utility meter, and reports the data back to a host computer system residing, for example, at a central office. Preferably, session-based communication using the meter protocol is implemented between the communications module and the meter, and packet switching is used between the communications server and the communications module through the network.

Abstract: Methods and apparatus for supplying power for use in metering electrical energy over a wide range of voltages with a single meter are disclosed. The wide ranging meter includes a processing unit for processing divided input voltage and a current component in order to determine electrical energy metering values. The processing unit is operable in response to supply voltages. A power supply, connected to receive the undivided voltage component, generates the supply voltages over the wide dynamic range. It is especially preferred for the power supply to include a transformer having first, second and third windings, wherein the undivided voltage component is provided to the first winding and wherein the second winding defines the output of the power supply. A switching member is connected to the first winding for permitting and preventing the flow of current in response to a control signal. A control member generates the control signal in response to the output of the power supply.

Abstract: A system and method for detecting a flicker of electrical energy provided via a service type to an energy meter. The system comprises a memory for storing a respective voltage threshold for each different service type; a digital signal processor for measuring a respective phase voltage for each meter element of the energy meter; and a microcontroller for retrieving the voltage threshold for the service type from the memory and comparing the measured phase voltage to the voltage threshold to determine an occurrence of flicker.

Abstract: An apparatus for metering electrical energy over a predetermined range of voltages within a single meter. The meter includes a divider network for dividing the voltage to generate a divided voltage. The divided voltage is substantially linear with minimal phase shift over the wide dynamic range. A processing unit processes the divided voltage and a current component to determine metered electrical power. A power supply receives the voltage component and generates a supply voltage from the voltage component over the predetermined range to power the processing unit. The power supply may include a transformer having first, second and third windings, so that the voltage component is provided to the first winding and the second winding defines the output of the power supply. A switching member is connected to the first winding for permitting and preventing the flow of current through the first winding.

Abstract: A 2-element, three voltage connection electronic energy meter is disclosed for measuring 3-phase electrical energy supplied by a 4-wire delta service without external potential transformers. The meter employs non-isolating voltage sensors for sensing the line voltages and includes and an automatic service type detector and isolation detector. The meter generates voltage and phase angle measurements for each of the two voltages sensed by the meter. The service type detector compares the phase angles to automatically determine the service type supplying the electrical energy to the meter. The isolation detector compares the two voltages to automatically determine whether or not the installation includes external potential transformers. If the service type is a 4-wire delta service and no external potential transformers are used at the installation for isolating the voltage signals, the meter doubles the voltage measured over the first of the two elements when generating power measurements.

Abstract: A system and method for improving the ability of an electronic meter to make measurements on signals to determine content of different frequencies, and harmonics of the fundamental frequency, of AC signals (voltages and currents). The line frequency is determined and compensated for prior to performing frequency-dependent parameter measurements or determining frequency-dependent parameters.

Abstract: An electronic energy meter for use with a 3-wire delta service having a resistive voltage divider for sensing and scaling the line voltages is disclosed. The resistive voltage divider includes three resistive dividers, one being associated with each phase of the electrical energy being metered. Each resistive divider includes a current limiter for reducing the current into the meter to a safe level when the meter electronics are operating at an elevated level, and a resistor for scaling the line voltage to a predetermined maximum peak-to-peak value. The scaled voltage that is generated has minimal phase shift, and therefore, does not require phase shift compensation prior to processing by a processing system of the electronic meter.

Abstract: A system for determining the service type to which an energy meter having meter elements is connected. The system includes a memory for storing reference information relating to different service types. The system determines which meter elements of the energy meter are active, and then determines relative phase angles and phase voltages of the meter elements. The relative phase angles are determined in to be in an ABC or a CBA rotation. Power quality monitoring is used in determining the phase voltages. The relative phase angles and phase voltages are compared to the reference information to determine the service type. The reference information includes services and scaling information, a nominal service voltage, a programmable potential indicator threshold, and a maximum and a minimum tolerance with respect to the nominal service voltage.

Abstract: Methods and apparatus for metering electrical energy are disclosed in an electronic meter which includes a first oscillator for generating a first clock signal to within a first accuracy and a second oscillator for generating a second clock signal within a second accuracy. A processor, operable in relation to a clock signal, measures time and periodically compensates for the accuracy of the first oscillator. The first clock signal is used for measuring time when power is applied to the meter and the second clock signal is used by the processor for measuring time when power has been removed from the meter. The accuracy of the first oscillator is compensated periodically in relation to a compensation factor stored in memory. In one embodiment, the processor includes a counter for counting from a first value to a second value in response to the first clock signal. In such an arrangement, the processor substitutes the first compensation factor for the first value.

Abstract: An electrical energy meter is provided with snap fit interlocking parts that eliminate the need for screws or fasteners. The current sensor, located within the meter, has a plurality of current conductors and a notched blade attached to each current conductor that functions as an interlocking component to the meter base without the need for additional fasteners. A circuit board used by the meter is attached to a plurality of integral posts projecting from the base and the periphery of the circuit board has a pair of spaced notches for connection to the ends of a radial communications antenna without the requirement for additional hardware.

Abstract: An apparatus and method for detecting tampering with an electrical energy meter comprising a disconnect switch, interposed into feeder lines that deliver electrical energy from a voltage source to an electrical load, which switches between an open circuit in which electrical energy is not supplied to the electrical load and a closed circuit in which electrical energy is supplied to the electrical load, a load-side voltage sensor, which provides voltage signals indicative of load-side voltage, and a microprocessor that determines whether a tamper conditions exists by determining whether the disconnect switch is open or closed, determining whether a load-side voltage is present, and, if the disconnect switch is open and a load-side voltage is present, indicating that a tamper condition exists. The tamper detection apparatus preferably includes a communications module, connected to the microprocessor, for providing a two-way communications interface to a remote location.

Abstract: A method for measuring an AC current in a conductor in which a DC current also exists includes the steps of (A) obtaining a first AC current measurement; (B) obtaining a measure of a power factor, fundamental frequency component, and second harmonic component; and (C) adjusting the first AC current measurement in accordance with an error value to obtain a corrected current measurement. The error value is determined as a function of the power factor, fundamental frequency component, and second harmonic component.

Abstract: A universal electronic energy meter for measuring electrical energy usage of a circuit having a 4-wire service is disclosed. The universal meter is operable with both 4-wire wye and 4-wire delta services without modification to the meter's hardware or software. The universal meter is further operable over a wide range of standard service voltages that are supplied in connection with 4-wire services. The universal meter includes a voltage divider network that senses the line voltages from the circuit and scales the line voltages to a voltage suitable for processing by the meter. The scaled voltage has a maximum peak-to-peak voltage irrespective of the particular standard service supplying the electrical energy to the circuit, and therefore, the voltage divider network is not reconfigured to accommodate a wide range of service voltages. The voltage divider network includes resistive dividers that scale the line voltage to provide a linear voltage with minimal phase shift.