Abstract: A method for determining the DC current flowing through an AC power meter. The internal impedance of the distribution transformer is first sensed, then the DC voltage in the AC voltage waveform is measured and finally the measured DC voltage is converted to DC current.

Abstract: An energy-to-pulse (E2P) converter for converting analog voltage and current measurements into digital power consumption readout that has an improved output frequency range and can eliminate the potential information loss in a multiple-wires and multiple-phases power distribution system without added complex hardware. The E2P uses a threshold value T in determining the output pulse count which represents the energy/power consumption. The energy consumption E is updated every cycle of a first clock rate F1 during which a power P calculation is performed following a voltage V and a current I analog-to digital conversion. The updated energy consumption E is then divided by the threshold value T to determine the number of pulses that correspond to the power consumption. The number of pulses are output at a second clock rate F2. In so doing, more than one pulse can be generated for each P calculation thereby improving the output frequency range.

Abstract: A method for measuring the impedance of electrical distribution equipment includes: applying a voltage at a first selected frequency to electrical distribution equipment, waiting a delay time for transient effects to settle, measuring current through the electrical distribution equipment, and selecting additional frequencies to repeat the steps of applying, waiting, and measuring.

Abstract: A method and apparatus for detecting a tamper event in an electrical power metering apparatus having power distribution and power service conductors connected to jaw contacts in a socket housing, the jaw contacts receiving blade terminals of an electrical service meter apparatus. A tamper event signature is detected based on a time relationship between separation of the ground circuit between the electrical power metering apparatus and the socket and the separation of at least one of the power distribution and power service blade terminals from the socket jaw contacts due to removal of the electrical service apparatus from the socket.

Abstract: An electric meter tamper detection system for sensing removal of an electric meter from a corresponding meter socket and for generating a tamper signal is disclosed. In this system, the tamper signal is relayed to a headend when the electric meter—connected in series with and monitoring current flour through at least one conductor—has been removed from the meter socket. At least one resistor is electrically connected to the line-side of the conductor. A light emitting diode is electrically coupled to the resistor and to the load-side of the conductor. A transistor receives the tamper signal from the light emitting diode when the electric meter is removed from the meter socket. A microprocessor is coupled to the transistor, receives the tamper signal from the transistor, and relays the tamper signal to said headend. Thus, the headend is immediately notified if and when the electric meter is removed from its meter socket.

Abstract: A power consumption system has

Abstract: A network of fixed RF transmitter modules, an RF repeater module and an RF collector module are located within a multi-unit facility for collecting water usage data from a plurality of water meters associated with the units within the facility and for uploading to a central billing center. Each water meter is coupled to a single RF transmitter module. Each RF transmitter module reads the water meter multiple times per day and transmits the data over a 418 MHZ carrier. One of a plurality of transceivers coupled to the RF repeater module receives the data and directs it to a storage medium in the RF repeater module. The RF repeater module temporarily holds the data and then repeats it on the RF carrier. The RF collector module receives the data through a transceiver coupled thereto. The data is stored in a storage medium of the RF collector module for retrieval by the central billing center.

Abstract: A metering device has a magnet with ten poles which is driven to rotate by a gear connected to a source of rotation that is proportional to fluid flow, the passage of time, or other phenomenon. A reed switch is mounted so that rotation of the poles of the magnet, into and out of a position adjacent to the reed switch causes the reed switch to open and close as the magnet rotates. The opening and closing of the reed switch causes a step change in voltage applied to an electronic device which increments a counter. A second reed switch spaced from the rotating magnet sufficiently so that it remains normally open can act as a sensitive device for detecting the presence of extraneous magnetic fields that might interfere with the operation of the first reed switch.

Abstract: An A-base utility meter cover assembly is described. The meter cover assembly is fabricated of a thermoplastic injection molding material, such as polycarbonate, and includes a base cover covered by a terminal cover. In one embodiment, the base cover includes a terminal block cavity for receiving a utility meter terminal block, and two locking tabs and a snap portion which engage openings through the terminal cover when the base cover and terminal cover are in an assembled configuration. In the assembled configuration, a dam and deflectors on the terminal cover are aligned with ribs on the base to form a continuous barrier against water flow into the terminal block cavity. The configuration of the locking tabs and snap portion also protect against tampering with meter electronics by preventing removal of the terminal cover.

Abstract: A utility meter cover apparatus is provided for protecting an existing utility meter casing from vandalism. The cover apparatus includes a generally tubular base adapted to be received over an end wall of the casing and permanently fixed to the casing by an adhesive or the like. The base includes an end opening that provides access to the end wall of the casing and to the window and any hardware mounted in the end wall. A cover is sized for receipt on the base over the end opening, and is movable relative to the base between a closed position covering the end opening and an open position exposing the end opening. A lock assembly is connected between the base and the cover, and is shiftable between a locked position in which the cover cannot be moved from the closed position and an unlocked position in which the cover can be moved to the open position to allow access to the end face of the meter casing.

Abstract: An electronic utility meter includes a sensor module, a measurement module, and a removable expansion module. The sensor module connects to the electrical system of a facility, and includes voltage and current sensors. The voltage and current sensors are operable to receive voltage and current signals from the electrical system and generate measurement 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.

Abstract: A portable energy meter test system for testing energy meters and other related instrumentation on-site is disclosed. The test system utilizes waveform generating circuitry to generate and transmit electrical waveforms to an energy meter to be tested, and sensing circuitry for sensing electrical characteristics corresponding to the transmitted electrical waveform. The test system includes a processor for evaluation and control of the testing procedure. A graphic touch screen is coupled to the processor for displaying information about the energy meter and for displaying test options to the user and allowing the user to control the testing process by touching the screen.

Abstract: An apparatus for determining loss of reference voltage (indicating possible tampering) in a 2-element electronic meter that includes a processor for determining electrical power from voltage and current signals, and a display for indicating an operating status of the meter. To determine if the reference voltage of the meter in a 3-wire delta or network installation has been lost, a measurement of the phase angle difference between the two phases is made. If the phase difference is equal to a predetermined value, the meter indicates on the display that loss of reference voltage and possible tampering has taken place. The apparatus may further be adapted to determine a length of time that this condition has occurred such that the appropriate enforcement and billing agencies may be informed.

Abstract: Method and apparatus facilitate improved sensing of tampering of an electrically powered device, such as an electric watt-hour meter installed at a residence for metering the amount of electric energy consumed at the residence. The detected tampering involves an effort to remove the electric meter from its power socket, to interrupt the metering of electric energy consumption, or to otherwise gain access for diverting electric energy. Removal of the electric meter from its power socket interrupts power to the meter. The method and apparatus senses motion of the meter and sets a “Tamper Flag” in a non-volatile memory. The “Tamper Flag” is saved (i.e., is not cleared from the non-volatile memory) if loss of power to the meter occurs within a predetermined period of time. The “Tamper Flag” is cleared if there is no loss of power to the meter within the predetermined period of time.

Abstract: A system for communication between multiple remote meter interfaces (RMI)s and a central office. The system includes multiple RMIs for reading meters and transmitting wireless data signals including meter readout information; multiple base repeater stations for receiving the wireless data signals where each particular base repeater station recognizes the wireless data signal only from particular RMIs that have been identified to the base repeater station, concentrates the information from the identified RMIS, and passes the concentrated information through a master base station and a wide area network (WAN) to a central office. The base repeater station includes a receiver for receiving the wireless data signal, a transmitter for passing concentrated information to the master station, and a microcontroller including an identification (ID) list including the IDs of the RMIs with which the base repeater station is enabled to communicate.

Abstract: An apparatus for testing an electrical device, having a high side terminal and a low side terminal, includes a power source which is connected to the high side terminal. A voltage monitor is also connected to the high side terminal to determine the voltage that is input to the device. Additionally, a current monitor is connected to the low side terminal to determine the current that passes through the device. A processor is connected to the power source, to the voltage monitor, and to the current monitor. Using the voltage input to high side terminal, and the through current from the low side terminal, the processor computes algorithmic functions which are compared with a predetermined value to establish an error signal. The apparatus then uses this error signal to control the input voltage from the power source to the high side terminal of the device.

Abstract: An electric meter tamper detection system for sensing removal of an electric meter from a corresponding meter socket and for generating a tamper signal is disclosed. In this system, the tamper signal is relayed to a headend when the electric meter--connected in series with and monitoring current flow through at least one conductor--has been removed from the meter socket. At least one resistor is electrically connected to the line-side of the conductor. A light emitting diode is electrically coupled to the resistor and to the load-side of the conductor. A transistor receives the tamper signal from the light emitting diode when the electric meter is removed from the meter socket. A microprocessor is coupled to the transistor, receives the tamper signal from the transistor, and relays the tamper signal to said headend. Thus, the headend is immediately notified if and when the electric meter is removed from its meter socket.

Abstract: An arrangement for electrically connecting an electrical utility revenue meter to a meter base includes at least two current blades that have a width that is less than the standard predefined current blade width. The meter base has one of first and second vertical alignment mechanisms, said first and second vertical alignment mechanisms cooperating with electrical utility revenue meters having current blades of a standard predefined width for effecting proper registration of the electrical utility meter with respect to the meter base. The arrangement of the present invention includes at least first, second, third and fourth current blades. At least two current blades each have a first edge aligned in registration with the first vertical alignment mechanism, and at least two current blades each have a second edge aligned in registration with the second vertical alignment mechanism.

Abstract: A device for detecting meter opening, the meter including at least a first structural element and a second structural element that are in a given position relative to each other when the meter is closed, said device comprising: a moving member connected to the first element and organized to take up a stable state or an unstable state as a function of the displacement of one of the structural elements relative to the other; holding means connected at least to the second element and co-operating with the moving member as a function of the displacement of one of the structural elements relative to the other, so as to hold said moving member in its unstable state and so as to enable it to go to its stable state; and detection means suitable for determining the state of the moving member and for emitting an opening signal when the moving member is in a predetermined state.

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: 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.

Abstract: A machine readable unit for meter devices of the type presenting a changeable, readable indicia proportional to a changeable input thereto, to include electric rate meters, gas meters, water meters, and other data registers, includes an assembly for displaying alphanumeric indicia in a machine readable format and an assembly for changing the displayed indicia responsive to input to the meter device.

Abstract: Magnetic shields for plastic molded electricity meter frames are positioned to substantially block external magnetic fields from adversely affecting operation of meter components. The shield can be utilized with either electromechanical or electronic energy meters. In an electromechanical watthour meter which employs an aluminum disk driven to rotate through a magnetic field produced by a retarding magnet, the meter frame includes an integrally formed retarding magnet shield and an integrally formed bearing shield. The shields are coextensive with the frame, and extend from an inner periphery of the frame toward the retarding magnet and the bearing, respectively. The shields are formed of a magnetically permeable powder, such as a ferrite powder mixed with the plastic material from which the meter frame is molded. The shields divert externally applied fields away from the magnetically sensitive components of the meter without adversely affecting meter accuracy.

Abstract: A voltage measurement instrument such as a digital multimeter is provided with transient overvoltage input protection. Internal walls are integrally molded with the instrument case and disposed in close proximity to the input receptacles and terminals to separate conductive surfaces and provide transient overvoltage barriers. Top and bottom wall portions are fitted together in tongue-and-groove fashion to increase the creepage and clearance path without increasing the linear distance between conductive surfaces. This arrangement also allows the instrument to maintain a low profile.

Abstract: A system of multiple remote meter interfaces (RMI)s and multiple base stations. Each base station concentrates meter reading information received from several RMIs and passes the concentrated information up through a wide area network to a central office. Each RMI may be field installed to communicate with only one base station. Each base station maintains an identification (ID) list having its own base station ID and the RMI IDs for the RMIs with which the base station is enabled to communicate. To install or reinstall a particular RMI without communicating with the central office, a field installer tool operated by a field installation or repair person establishes communication with the base station using the base station ID, then directs the base station to add the RMI ID for the particular RMI to the ID list.

Abstract: A sensor assembly and method of forming the sensor assembly for sensing count and tamper, where the count is related to an energy field having a gradient along an axis of sensitivity and where the tamper is related to a static energy field and where the energy comprising the static energy field is the same type as the energy comprising the energy field having a gradient, includes an energy gradient detector that has at least a first sensor spaced apart from and communicably coupled to a second sensor along the axis of sensitivity. A static energy detector that has at least a first shielded sensor, the shielded sensor being substantially shielded from the energy field having a gradient and from the static energy field. A second unshielded sensor is communicably coupled to the shielded sensor. The invention further includes a method of detecting a spatially varying magnetic field.

Abstract: A meter sensor light tamper detector includes at least one light emitter and one or more sensors. The sensors have some parameter, i.e., conductivity in the case of phototransistor sensors, to provide an indication that they are in the presence of light. The system also includes a microprocessor which is capable of independent control of the light emitter and the sensors, and can determine the state of the electrical parameter, i.e., conductivity or nonconductivity, of the sensors. The microprocessor determines whether the sensors are being tampered with by checking the state of the sensors when a particular light condition is known to be present or absent.

Abstract: A semiconductor device has a first-conduction-type semiconductor substrate (19), an internal circuit including a vertical bipolar transistor (18) formed in a second-conduction-type semiconductor layer (20), and a protective element (14). The protective element comprises a first-conduction-type diffusion layer (22a) formed at an upper part of a second-conduction-type semiconductor layer (20a) disposed on the semiconductor substrate (19), and a second-conduction-type diffusion layer (27, 30) formed in the first-conduction-type diffusion layer (22a). The diffusion layer (27, 30) is at least partly deeper than an emitter diffusion layer (23) of the vertical bipolar transistor (18).

Abstract: A test fixture provides ESD protection to electronic switching circuitry in a universal grid type fixture having test probes arranged for electrical contact with a printed circuit board under test and in which test signals are sent between the circuit board and a high speed electronic test analyzer through intervening switching circuits. The test fixture includes a movable probe plate, a test probe mounted in the probe plate, the test probe including a movable plunger for making electrical contact with a printed circuit board during a test cycle, the plunger being movable between a first position and a second position, and a ground plane on the movable probe plate connected to electrical ground, the probe plunger having a ground plane contact element that contacts the ground plane in said first position of the plunger and which moves out of the contact with the ground plane when the plunger moves to the second position.

Abstract: An intelligent power consumption monitoring and control system is provided. The system is composed of a computer with management software, a group of communication controllers consisting of transmitters, receivers, and modems and insulators. The communication controller connects to a data exchanger in the user's intelligent meter which is composed of a meter case, a data display, and a PCB board. A buzzer, a select button, and an alarm reset button are designed on the face of the meter case. On the PCB board, there is a single chip microcomputer, program storage, data memory, a transmitter and receiver module, an A/D and D/A conversion module, a theft control, a power line balance detection module, as well as a power supply module. The invention solves many problems in current power supply management and is an effective total automatic power supply management system with a computer network.

Abstract: A multimeter is provided having an erroneous input prevention mechanism that allows more than one mode to be assigned to an input terminal hole located in a central section of a shutter board based on movement of a rotary switch. When the rotary switch is rotated, the first and the second drive-side protrusions formed at separate locations from the selector push away the first or second slave-side protrusions in the slave shell to rotate the shutter board about the center at the negative common terminal hole. Thus, only a specific terminal hole is in the open state. Even when the rotary switch is rotated to a predetermined position, the shutter board does not rotate to leaving the first input terminal hole in the open state.

Abstract: A system and method for detecting fault conditions within a vehicle recording device are disclosed herein. The fault detection technique may be implemented in a vehicle in which are incorporated one or more vehicle sensors for monitoring one or more operational parameters of the vehicle. A recording device disposed within the vehicle is used to collect vehicle operation data produced by the one or more vehicle sensors.The fault detection technique of the invention contemplates storing a current time value at regular intervals during periods in which the recording device is provided with a source of main power. Time differences are determined between consecutive ones of the stored time values, and the time differences compared to a predetermined maximum value. A power loss fault condition is registered when at least one of the time differences exceeds the predetermined maximum value.

Abstract: A method and device, including a portable embodiment, for the automated inspection of devices having different visual changeable and non-changeable indicia on the faces thereof. Specific devices include meters, particularly electric usage meters, for detection of tampering, for improving efficiency of maintenance procedures and for usage in reading the meters for billing purposes. Meters of various heights, configuration and construction are fixed into designated positions and are inspected by visual computer-linked camera scanning, to determine meter periphery and a location reference point, and imaging of identifying portions of meter faces relative to the determined location reference point. The identifying portions are compared with correlative templates of existing meter types, stored in computer memory. Identification of specific meter type permits exact location and subsequent OCR identification of the specific meter number (with use history) and parameters (voltage, amperage, wire connections etc.

Abstract: A wide area communications network communicating data from a plurality of network service modules through a plurality of remote cell nodes and intermediate data terminals to a central data terminal. The wide area communications network collects network data generated by a plurality of physical devices such as gas, water or electricity meters, located within a geographical area. The wide area communications network is a layered network having a hierarchical communications topology. The central data terminal controls network operation. Intelligence exists at all layers of the network, thereby easing the workload of the central data terminal. The intelligence attributed to each module is a function of the application of that module.

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 electric meter includes a housing, a switch positioned within an opening in the housing, a hinge pin having a first cross-sectional shape and being connected to the housing, and a switch cover having a passageway receiving the hinge pin therein and permitting pivotal movement of said switch cover between a closed position and an open position. The passageway has a second cross-sectional shape cooperating with the first cross-sectional shape of the hinge pin for locking the switch cover in the open position. The hinge pin preferably includes a generally cylindrical shaft and a ridge extending longitudinally thereon to define the first cross-sectional shape. Accordingly, the passageway of the switch cover is preferably defined by a generally cylindrical portion with a first longitudinally extending channel in communication therewith to define the second cross-sectional shape.

Abstract: Apparatus and methods are claimed for detecting tampering with a load management terminal, wherein the terminal has a load control relay coupled to a power line for selectably decoupling the load from the power line. One embodiment of the claimed apparatus for detecting tampering comprises a current sensor coupled to the load control relay for sensing whether load current is flowing through the load control relay contacts when the contacts are closed. A timer is provided for measuring elapsed time during which no current is sensed flowing through the closed contacts. An indicator provides an indication of tampering when the elapsed time measured by the timer exceeds a pre-determined time limit. Preferably, in this embodiment, the current sensor comprises a voltage detector coupled to the control coil of the relay for detecting whether an AC voltage has been induced in the control coil by the load current.

Abstract: An electronic meter for measuring electricity includes a magnetic shield positioned adjacent each outermost toroidal coil of electrical current sensors to thereby resist tampering by a magnetic field applied from outside the meter housing. The magnetic shield has an arcuate cross-sectional shape corresponding to the outermost coil portion and has a predetermined arc length covering only a predetermined portion of the outermost coil portion. The shield preferably has a semicylindrical cross-section shape thereby covering only half the toroidal coil.

Abstract: A device for detecting tampering of a utility meter includes sensors to detect a positional displacement of the meter and loss of power to the meter. On sensing a positional displacement of the meter, indicative of an attempt to remove the meter, a timer is activated to enable sensing a power loss to the meter. In response to detection of a power loss during the time period defined by the timer, an indication is stored in a nonvolatile memory of the tamper event. In response to loss of power with or without a detection of tampering, required parameters including utility consumption data are stored in nonvolatile memory. Remote access to and data retrieval from the nonvolatile memory and system are provided over telephone lines, power lines, or a radio frequency circuit.

Abstract: An electric meter has reduced torque needed during relative rotation of a cover and base during a predetermined portion of rotation between initial and locked positions to thereby facilitate securing of the cover and base together at a predetermined seating torque. The torque reduction is preferably provided by a plurality of base ridges connected to the base mating surface adjacent respective clip receiving slots, and a plurality of cover projections connected to the cover mating surface. The cover projections slidably contact adjacent base ridges on the base mating surface to thereby reduce friction during the portion of rotation between the initial and locked positions. A gasket is preferably positioned between the base mating surface and the cover mating surface.

Abstract: A system for detecting the presence of an average dc current component in a load comprising a current transformer 10 for supplying a signal representative of the current, and a comparison means 12 and 13, for example a microprocessor and associated RAM, for comparing values of the current taken at time intervals corresponding to a phase interval of substantially n.pi., where n.pi. is an odd integer, of the ac periodic supply signal, so as to determine the presence of a dc current component caused by rectification of the supply. In one embodiment, the signal from a voltage detecting means 14-18 can be used to synchronise the sampling of the current at the correct phase.

Abstract: A device for protection of a digital multimeter from misinsertion of an input plug. The device prevents misinsertion of the input plug into an input core having no concern with a selected function and generates an alarm sound when a function switch is unconsciously rotated disregarding insertion of the input plug in an input core. The device comprises a plug misinsertion preventing unit for preventing the input plug from being inserted into specified one of the plug inserts when a function except a specified function is selected, the specified function corresponding to the specified plug insert. An alarm generating unit for alarming when the function switch is operated in order to change a function under the condition that the input plug is continuously inserted in the specified plug insert. The plug misinsertion preventing unit comprises a rotating plate and a shielding layer cooperating with the rotating plate. The shielding layer selectively shields the specified plug insert.

Abstract: A hardened metallic ring is mounted over the exterior sidewall of the shell portion of a watthour meter socket adapter. The ring has overlapped ends which are welded together to form a circular ring with a diameter approximate the diameter of the shell. In another embodiment, a radially outward flange is formed on one annular edge of the ring to cover a peripheral edge flange of the base of the socket adapter.

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: A coupling circuit for a multimeter adapted to perform multiple measurements includes a thermistor and constant current sources in series between an instrument input terminal and an instrument circuit adapted to source current for ohms measurements. Varistors shunt the constant current sources and are thermally coupled to the thermistor. An initial inrush of current is controlled by the constant current sources and when the voltage across a constant current source reaches the knee voltage of the paralleled varistor, the varistor shunts the constant current source and provides heat to the thermistor for insuring the latter will transition to its high resistance state. The thermistor then drops a substantial part of the input voltage, effectively disconnecting the low impedance ohms circuit from the input terminals and protecting the constant current source circuitry and varistors from extended application of high voltage.

Abstract: An apparatus for contactless data and energy transmission and includes a stationary part having device for transmitting and receiving data and device for generating energy. A movable part has a plurality of rectifier devices each with at least one output and modulators each being connected downstream of a respective one of the rectifier devices. A first pair of coils is connected to the device for transmitting and receiving data and to the rectifier device for transmitting data from the stationary part to the movable part. A second pair of coils is connected to the device for generating energy and to the rectifier device for transmitting energy from the stationary part to the movable part. The coils in the stationary part are arbitrarily associated with the coils in the movable part, and data is transmitted from the movable part to the stationary part by a load variation at the coil of the movable part not being used for energy transmission.

Abstract: A load measuring device includes a sensor for detecting power consumption surges by detecting a zero voltage point in the alternating voltage of an electrical apparatus, detecting the zero current point in the alternating current of the apparatus least remote in time from the detected zero voltage point, and measuring the interval between the two zero points.

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: In multimeters for the selective measurement of different measurable variables having test signals that are detected by the multimeter through the use of various input circuits assigned to respective measurable variables, an input circuit can be connected which is not suitable for an input variable set at a measurement range switch. In order to draw the attention of the operator at least to an error that the operator is responsible for, at least one auxiliary circuit is provided and fed through the measurement range switch in such a manner that a fixed assignment to a particular input circuit and consequently to a particular measurable variable results. The assignment is dependent on a switch position. Inserted in the auxiliary circuit is at least one function generator which triggers a function or a combination of a plurality of functions upon actuation, which is preferably achieved by closing the auxiliary circuit. This counteracts the operating error in switching the measurable variable.

Abstract: A voltage rotation indicator for testing the phase sequence of live multi-phase electrical power is mounted within a housing. The housing is provided with structure for removably mounting the indicator on a meter box or can during voltage rotation testing. Contact plungers extend from the housing and contact meter jaw test points in the meter box during testing. Field personnel are thus not required to insert their hands into the meter box to attach test clips to the live circuit.