Abstract: An electronic residential electricity meter includes a base assembly having a main body with a current transformer mounted thereto. A first conductor is mounted through a window of the current transformer. The current transformer being operable in the presence of a direct current. The meter also includes an electronic module that has only one printed circuit board and a microcomputer for executing meter data operations. The current transformer and the first conductor are in electrical communication with the electronic module.

Abstract: The present invention, in one embodiment, is a method for operating an electronic electric meter having current and voltage sensors configured to generate measurements of current and voltage, respectively; a microcomputer coupled to the current and voltage sensors and having on-chip masked read only memory (ROM); and a nonvolatile, alterable memory coupled to the microcomputer. The method includes steps of: storing vectors pointing to program portions of the ROM in the non-volatile memory; and using the stored vectors to operate the microcomputer to execute the program portions stored in the ROM to control operation of the meter.

Abstract: The present invention, in one embodiment, is a method for input/output (I/O) board addressing and communications in an electronic electric meter having a microcomputer. The method includes steps of providing interchangeable I/O boards of an electronic electric meter with type identifiers; and determining, using a microcomputer of the meter and the type identifier of the I/O board, a type of interchangeable I/O board being utilized in the meter.

Abstract: An apparatus and method for creating a secure program history log for a programmable device including a microprocessor, at least one communications port for communicating with the microprocessor and at least one memory device electrically connected to the microprocessor. The memory device includes a program history log, and the method includes communicating program parameters to the microprocessor, creating a log entry utilizing the microprocessor and the program parameters, and writing the log entry into the program history log utilizing the microprocessor.

Abstract: The present invention, in one embodiment, is a method for metering energy consumption with an electric meter. The method includes steps of: generating metering quantities for a plurality of phase voltages from a multiphase voltage source, including generating revenue-related data; monitoring voltage changes on at least one of the phase voltages; and performing a predetermined task in response to a voltage change on at least one of the phase voltages while continuing to generate revenue-related data.

Abstract: A base barrier for an electronic meter assembly including a base assembly having a plurality of wire leads extending therefrom and a revenue guard board for monitoring phases of a meter power supply. The base barrier includes a body configured for mounting to the base assembly and further configured for retaining the revenue guard board thereto. In her aspect, the base barrier includes at least one wire management member therein.

Abstract: The present invention, in one embodiment, is a method for defining meter data calculations in an electronic electric meter. The method includes steps of: storing a set of predefined data calculation instructions in a non-volatile memory of the meter; storing a first set of vectors in a memory of the meter, the vectors pointing to data calculations of the set of predefined data calculation instructions; metering a plurality of electrical quantities of a power source; and controlling calculations performed on the metered electrical quantities in accordance with the data calculation instructions pointed to by the first stored set of vectors.

Abstract: A base barrier for an electronic meter assembly including a base assembly having a plurality of wire leads extending therefrom and a revenue guard board for monitoring phases of a meter power supply. The base barrier includes a body configured for mounting to the base assembly and further configured for retaining the revenue guard board thereto.

Abstract: A method for measuring electricity usage that includes steps of: coupling a sensor to a power source; converting a signal from the sensor to a digital measurement signal; using a microcomputer to determine quantities indicative of electricity consumption from the digital measurement signal; and using a nonvolatile, reprogrammable memory coupled to the microcomputer to control the microcomputer in determining the quantities indicative of electricity consumption.

Abstract: The present invention, in one embodiment, is a method for controlling data flow in an electronic electric meter. The method includes steps of measuring current and voltage of a power source; determining a set of internal quantities using the measured current and voltage; using the set of internal quantities in conjunction with a set of functions to determine measurement profile quantities; and storing the determined measurement profile quantities in registers within the meter.

Abstract: A method is described for measuring a plurality of line voltages using a measurement circuit, the method including the steps of reducing each line voltage over a first impedance; providing a second impedance between each of the reduced voltages and a measurement circuit common reference point; coupling the common reference point to a voltage line N using a third impedance; and determining line voltage values using measurements of the reduced voltages. The above-described method provides impedance between voltage line N and measurement electronics and thus prevents transient voltages from entering the measurement circuit.

Abstract: An apparatus and method for creating a secure program history log for a programmable device including a microprocessor, at least one communications port for communicating with the microprocessor and at least one memory device electrically connected to the microprocessor. The memory device includes a program history log, and the method includes communicating program parameters to the microprocessor, creating a log entry utilizing the microprocessor and the program parameters, and writing the log entry into the program history log utilizing the microprocessor.

Abstract: Methods and apparatus for controlling operation of a low frequency oscillator upon reset of a microcomputer to achieve faster start-up time are described. In one aspect, the present invention is directed to a microcomputer having an oscillator input port, an oscillator output port, and an oscillator control port, and an oscillator coupled to the microcomputer oscillator output, input, and control ports. The microcomputer is programmed to control the output on the oscillator control port so that upon reset, the output transitions from a low state to a high state in accordance with a preselected frequency for a preselected period of time. More particularly, and in one exemplary embodiment, the microcomputer controls the output on the oscillator control port upon reset so that for a preselected cycle, the output is high for approximately about one-half cycle, low for approximately about one-half cycle, and then high for approximately about one-half cycle.

Abstract: A method and apparatus for transmitting signals according to the present invention between electrical metering devices and a system control center includes a mobile node. The mobile node communicates with the electrical metering devices operably connected to a distribution transformer and transmits the signals received from the electrical metering devices to the system control center while the mobile node is in the field and removed from the system control center. The mobile node may then be relocated in the field within the electrical power distribution system so as to communicate with the electrical metering devices operably connected to another distribution transformer. Thus, a single mobile node may communicate with the electrical metering devices connected to a number of distribution transformers so as to decrease the number of fixed nodes employed by a communications system of an electrical power distribution system.

Abstract: In one embodiment, the present invention is an algorithm implemented in a microprocessor-controlled system which, for example, is disposed within an energy meter housing. Particularly, the microprocessor is coupled to a communications interface which receives and transmits messages on a power line or some other external communications media. Upon receipt of a message, the commands contained in the message are read. If a command corresponds to a "buffer and lock" command, then a timer operated by the microprocessor starts to run. For example, if data to be retrieved from the system is data which is erased from system memory when read therefrom, just prior to reading such data, a buffer and lock command is transmitted by the external communication device. Upon receipt of such command, the microprocessor initiates running of a timer and the data is read from the meter. The data also is copied to a buffer, e.g., a RAM memory location.

Abstract: An electronic watthour meter is digitally configurable to operate as several different types of watthour meters for metering electrical energy from a variety of different electric utility services. Automatic scaling of line input currents is provided to scale the voltage input to an analog to digital converter over selected ranges such that low level and high level input signals are measured in an optimum range. A digital signal processor is employed to calculate values for metered electrical energy and output pulses, each proportional to a quantum of energy flowing in the circuit being metered. The processor calculates the value of DC offset errors inherent in the various analog circuits of the meter and uses that value in the calculation of metered electrical energy to compensate for such offset errors. The meter employs automatic and manually initiated test functions for testing the operation of the processor and other critical circuits in the meter.

Abstract: An electronic watthour meter is digitally configurable to operate as several different types of watthour meters for metering electrical energy from a variety of different electric utility services. Automatic scaling of line input currents is provided to scale the voltage input to an analog to digital converter over selected ranges such that low level and high level input signals are measured in an optimum range. A digital signal processor is employed to calculate values for metered electrical energy and output pulses, each proportional to a quantum of energy flowing in the circuit being metered. The processor calculates the value of DC offset errors inherent in the various analog circuits of the meter and uses that value in the calculation of metered electrical energy to compensate for such offset errors. The meter employs automatic and manually initiated test functions for testing the operation of the processor and other critical circuits in the meter.

Abstract: An electronic watthour meter is digitally configurable to operate as several different types of watthour meters for metering electrical energy from a variety of different electric utility services. Automatic scaling of line input currents is provided to scale the voltage input to an analog to digital converter over selected ranges such that low level and high level input signals are measured in an optimum range. A digital signal processor is employed to calculate values for metered electrical energy and output pulses, each proportional to a quantum of energy flowing in the circuit being metered. The processor calculates the value of DC offset errors inherent in the various analog circuits of the meter and uses that value in the calculation of metered electrical energy to compensate for such offset errors. The meter employs automatic and manually initiated test functions for testing the operation of the processor and other critical circuits in the meter.

Abstract: A current sensor employs a main resistor of a low temperature-coefficient material for producing a voltage drop proportional to a load current therein. A second resistor, also of a low temperature-coefficient material, and preferably having a resistance substantially exceeding that of the main resistor, is connected in parallel with the main resistor. The current divides between the main and the second resistors according to the ratio of their resistances. An output signal, reduced at least in accordance with a ratio of resistances of the first and second resistors, is obtained from the second resistor. Resistive heating of the main resistor is reduced by using a short path length in the direction of current flow and as large an area transverse to the direction of current as possible. A current transformer may employ the second resistor as a primary to step down further the current in the output signal.