A tamper switch mechanism utilized in security interface devices such as keypad installations to render them tamper-resistant, wherein the devices are generally connected to burglar alarm and fire alarm systems. More particularly, provided is a conductive tamper switch which is installed in a security interface device, such as a keypad, which upon an unauthorized attempt to dislodge the device or keypad from a wall or surface on which it is mounted, will trigger an alarm or generate a warning signal at a monitoring site indicative that an effort at tampering with the device has been effected. Also disclosed is a method of providing the tamper switch mechanism in a security interface device, such as a keypad installation.

Conductive tamper switch for security devices

Data signals are communicated between a power line and a computer, wherein the power line provides power to the computer via a distribution transformer and the computer is in communication with a wireless communication path. A first data signal is communicated with the power line. A conversion is made between the first data signal and a second data signal capable of being communicated wirelessly. The second data signal is wirelessly communicated with the wireless communication path.

Data communication over a power line

A system for modifying the functionality of intelligent electronic devices installed and operating in the field is disclosed Each of the intelligent electronic devices operates with a software configuration to monitor electrical energy A copy of the software configurations may be maintained in a database Changes to the operation of one or more of the intelligent electronic devices may be made as a function of modifications to the database

Systems for in the field configuration of intelligent electronic devices

An electronic electric meter for use in a networked automatic meter reading environment. The electric meter retrofits into existing meter sockets and is available for new meter installations for both single phase and three phase electric power connections. The meter utilizes an all electronic design including a meter microcontroller, a measurement microcontroller, a communication microcontroller and spread spectrum processor, and a plurality of other communication interface modules for communicating commodity utilization and power quality data to a utility. The electric meter utilizes a modular design which allows the interface modules to be changed depending upon the desired communication network interface. The meter measures electricity usage and monitors power quality parameters for transmission to the utility over a two-way 900 MHz spread spectrum local area network (LAN) to a remotely located gateway node. The gateway node transmits this data to the utility over a commercially available fixed wide area network (WAN). The meter also provides direct communication to the utility over a commercially available network interface that plugs into the meter's backplane or bus system bypassing the local area network communication link and gateway node.

Electronic electric meter for networked meter reading

A device and method for communicating user data and utility metrology data over a power line is provided. In one embodiment, the method includes measuring a utility parameter to provide the utility data; storing the utility data in memory; transmitting the utility data over the power line; receiving first data via the power line from a first device; and transmitting the first data over the power line to a second device. In addition, the method may include receiving the first data and transmitting the first data with different encryption keys and also determining if the first data includes control data.

Power line communications module and method

An electronic utility meter includes a sensor module (12), a measurement module (14), and a removable expansion module (100). The sensor module connects to the electrical system of a facility, and includes voltage and current sensors (15). The voltage and current sensors are operable to receive voltage and current signals from the electrical system and generate measurements signals therefrom. The measurement module includes a measurement circuit operable to receive measurement signals and generate energy consumption data therefrom. The measurement module further includes a device for communicating information relating to the energy consumption data. The measurement module is configured to couple to the sensor module to connect the measurement circuit to the voltage and current sensors. The removable module is interposed between the sensor module and the measurement module. The removable module operably couples the measurement circuit to the voltage and current sensors.

Expansion module for modular meter

A current sensing device includes a secondary coil positioned within the curved portion of a U-shaped primary conductor or coil. The secondary coil is surrounded by a non-ferromagnetic metallic shield to prevent capacitive coupling between the windings of the secondary coil and other nearby metallic objects. A nonconductive material is integrally formed about the U-shaped conductor and provides a cavity for receiving the secondary coil an shield in a predetermined position with respect to the U-shaped conductor. A flux guide of ferromagnetic metal, formed in an elliptical-cylindrical shape, surrounds the U-shaped conductor and the secondary coil to provide a flux steering effect to steer flux around the secondary or pick-up coil. The current sensing device is useful in measuring current in electrical utility power monitoring or watthour meter applications.

Shielded current sensing device for a watthour meter

An electronic utility meter includes a sensor module and a removable measurement module. The sensor module connects to the electrical system of a facility and includes voltage and current sensors. The voltage and current sensors is operable to receive voltage and current signals from the electrical system and generate measurement signals therefrom. The sensor module further includes an electrically safe interface. The removable measurement module includes a measurement circuit operable to receive measurement signals and generate energy consumption data therefrom. The measurement module also includes a device for communicating information relating to the energy consumption data. The electrically safe interface of the sensor module operably connects the voltage and current sensors to the measurement circuit, and further prevents physical contact of a human operator with the received voltage and current signals from the electrical system when the measurement module is removed from the sensor circuit.

Low profile modular revenue meter

A watt-hour meter employs a power factor compensation technique that inserts a delay into the digitized current or voltage sample stream. An exemplary embodiment of the present invention includes an electronic watt-hour meter comprising a voltage sensor, a current sensor, a conversion circuit, and a processing circuit: The voltage sensor generates a voltage measurement signal responsive to a voltage provided to a load. Similarly, the current sensor generates a current measurement signal responsive to a current provided to a load. The conversion circuit further comprises: a first converter connected to the voltage sensor for generating sampled voltage data stream based on said voltage measurement signal; a second converter connected to the current sensor for generating a sampled current data stream based on said current measurement signal, and a phase correction circuit. The phase correction circuit is connected to one of the first and second converters and inserts a delay into one of the sampled voltage data stream or the sampled current data stream. The processing circuit is operably connected to the first and second converters, and receives information indicative of the sampled voltage data stream and sampled current data stream subject to any delay inserted by the phase correction circuit. The processing circuit then generates power consumption data from the sampled voltage data and sampled current data.

Watt-hour meter with digital per-phase power factor compensation

An electricity meter includes a current sensor, an analog to digital (A/D) converter coupled to the current sensor, and a processor coupled to the A/D converter. The current sensor and the A/D converter cooperate to generate a digital current signal having a waveform representative of the current waveform on the power lines connected to the electricity meter. The processor is operable to analyze a digital current waveform signal produced by the current sensor and A/D converter to detect a rectified (DC) load. In particular, the processor perform analysis on the digital current signal to generate a peak positive current value and a peak negative current value, and then detect the presence of a rectified load coupled to the power network based on said peak positive current value and said peak negative current value.

John T. Voisine

Papers

Expansion module for modular meter

Shielded current sensing device for a watthour meter

Low profile modular revenue meter

Watt-hour meter with digital per-phase power factor compensation

DC load detection in an electric utility meter