Showing papers on "Electricity meter published in 1987"

Magnetic tamper detector

Abstract: An electric meter is provided with a magnetically sensitive switch and a means for detecting the activation of the switch. A program is provided for sensing, recording and transmitting the status history of the magnetically sensitive switch to a remote device. The electric meter is connected in signal communication with a power line communication system and provided with the capability of transmitting and receiving messages in conjunction therewith. The electric meter senses the presence of a strong magnetic field in the region of the electric meter and, if other appropriate flags are not set, this information is used to determine that an effort to tamper with the meter by using magnetic fields has occurred.

Electricity meter with solid-state circuits

Abstract: Metering apparatus which employs a structure conforming to long accepted industrial standards but which is adapted to meet the requirements for highly versatile solid-state meter circuits having a multitude of outputs both in terms of electrical signals and visual display. The meter structure is provided an EMF and RF barrier coupled to through the interconnection of the meter cover to neutral reference. Further, a key actuated switching input is provided through the cover face of the meter with the use of a pattern of contact surfaces positioned on the inner surface of the face. These surfaces cooperate with spring biased contacts arranged to achieve proper contact with them when the meter cover is rotated into its latched orientation. A separate terminal block is provided which is coupled through a multi-lead connector to the meter circuit and which provides discrete individual terminal outputs readily wired by utility personnel trained in the use of older mechanical metering systems.

Digital energy meter

Abstract: A digital energy meter for providing energy measurements of nonsinusoidal waveforms. Voltage and related current components of a digitally sampled waveform are multiplied to form a product representative of instantaneous power. The products are summed or accumulated over a first time period, and the sums then accumulated over a second time period to form a second sum representative of total power over the second time period. An energy measurement is then obtained by an algorithm which requires only a simple division by a power of two.

Supported thin foil stripper and simple non-obstructing power meter for a space based neutral particle beam system

Abstract: A thin foil stripper and simple non-obstructing power meter for a space based neutral particle beam system consisting of a panel of thin foils supported by resistance wires and mounted on a wheel or disk in such a manner that the surface used for stripping the beam may be changed or replaced periodically. The power meter consists of four resistors arranged in the form of a bridge, a power source (battery), a detector (voltmeter), and a display unit (recorded, etc.). Two of the resistors consist of the wires which support the foils and are nearly identical. The other two resistors are used to balance the bridge. When one of the strippers is exposed to the neutral particle beam, the support wire is heated, the resistance changes, and the bridge becomes unbalanced. The magnitude of the voltage produced is proportional to the power in the beam. The power meter is non-obstructing.

Electrical service installation

Abstract: An electrical service installation has a main electricity meter (33), which is accommodated in a mains connection box, and a line protection circuit breaker and/or residual current device (20, 21, 22), which is assigned thereto, for in each case at least one sub-load (13). An additional, electronic power measurement device (12, 14; 23 to 28) is assigned to each line protection circuit breaker and/or residual current device (10; 20, 21, 22) assigned to a sub-load (13) or to each group of line protection circuit breakers or residual current devices assigned to a load (13). In consequence, cost-effective sub-meters can be provided which do not need calibration. A correction factor is determined by comparing the sum of the readings of the individual sub-meters with the reading of the main electricity meter and the sub-meter readings are multiplied by this correction factor, that is to say are corrected. This service installation is used especially where calibrated and expensive secondary electricity meters are uneconomic.

A simple laser power meter dependent on photoacoustic effect

Abstract: The design and fabrication of a simple laser power meter dependent on the photoacoustic effect is described. This power meter has a sensitivity of 1 mV/3.5 mW laser power and the microphone has a sensitivity of 10 mV/Pa. It can be used in any wavelength region and its calibration is easy.

Power meter for optical efficiency measurements of laser-induced plasmas

Abstract: A power meter was constructed to measure the power being deposited in transient laser-induced plasmas (LIP). The design rejects the radiation scattered from the laser beam by the LIP and that transmitted past the LIP. The power meter is constructed from a small metal-capped flask placed in an evacuated chamber. The steady-state heat production in the flask is determined from measurements of the temperature gradient on a thermal resistance connecting the top of the flask with a heat sink. The design worked well and should be applicable to a wide variety of situations if the dimensions of the system are adjusted to compensate for power levels substantially different from those used here.

Portable test unit for ac/dc electric meters

Abstract: The utility model relates to a portable test unit for AC/DC electric meters, comprising an electrical voltage part and an electric current part. The electrical voltage part is a circuit formed by the primary elements such as a regulator of the thickness of the electrical voltage, an elevating transformer, a voltage limit conversion, a double-compensation type voltage transformer, a rectifier filter, etc. The electric current part is a circuit formed by the primary elements like a regulator of the thickness of the electric current, a phase shifter of conversion type of the voltage division and quadrant, a current generator, a conversion of the tie line of the electric current, etc. All components can be arranged in a suitcase, and carry to the job site conveniently to in-situ test the indicating meter of the electrical measurement.

Semi-Automatic Meter Reading

Abstract: Meter reading in the electric utility Industry has been investigated from many different viewpoints. It is typically concluded that it is difficult to achieve more cost efficiency than the system widely used at present; manual reading at the uers location once a month. This paper will review the development of a new approach to more efficient meter reading.

Anti-tamper electric meters

Abstract: A combination of an electric kWh meter (1) and a house service cutout (2), in which the latter has terminals (3, 6, 10) which align with those (4, 8, 5) of the meter and is disposed immediately beneath and substantially in contact with the meter, with conductors (11, 12, 13) extending directly between the cutout and meter terminals By this means exposed interwiring is avoided and the possibility of fraudulent interference substantially prevented

Milimeterwave full band power meter

Abstract: A new type of calorimetric milimeter wave full band power meter adopts the double symmetrical transmission system and its two terminations are designed of the same structure. In the waveguide there is a calorimetric load and a piece of metal made as fin-like wire. Carbofrax and beryllia are used as the material of calorimetric load. The power meter has simple structure, wide working band and wide range of power and short time constant. One power meter of this type can replace 5-7 sets of traditional power meters.

Solid state electricity meter with an electromagnetic meter display

Abstract: The essential loads of an electricity meter (light-emitting diode and electromagnetic meter count display) have hitherto been activated at the same time with the consequence of high current loading on the mains section. The invention relates to reducing the maximum current consumption of an electricity meter. In the arrangement according to the invention, current (I) and voltage (U) are supplied via a matching stage (1) to a multiplier (2) and its output signal is supplied to a quantiser (3). The power-proportional output signal of the quantiser (3) is supplied to an electromagnetic meter count display (4) and via a block (5) to an optical display (6). The block (5) prevents meter count display (4) and optical display (6) from being activated at the same time. The result is that the maximum current consumption is reduced and that the mains section can be dimensioned for less maximum current delivery.

Programmable time sharing and metering controller for electric power

Abstract: The utility model relates to a programmable time sharing and metering controller for electric power used to save energy and realize a best time-sharing measuring standard, belonging to a special charging electric meter apparatus. The utility model is provided with one read-write register RAM to store on-off control words of the electric meter, a programme counter, a programmer to control the RAM gating address, and a 24 hours electronic clock synchronized with the program counter to display real-time hours. The utility model also comprises a loss-protect protector to prevent programs from keeping in order, an executor to control three electric meters, such as 'Peak', 'valley 'and 'flat ', a standby power, etc. The utility model has the advantages of simple structure, convenient operation, etc., and can compile and modify programs at any time.

Geomagnetic universal electric meter

Abstract: The utility model discloses a geomagnetic universal electric meter. General pointer type electric meters all have the disadvantages of complicated structure, high cost, and big volume. The rotating part of the meter head of the utility model is composed of a magnet having the advantages of strong magnetic performance, good protecting magnetic performance, and agile rotation, and a pointer on the magnet. The switching on coil curl of the meter head is a fixed coil curl which is lightly bigger than the magnet. The utility model has the advantages that the geomagnetic universal electric meter can be made into an electric meter for the special purpose of the physical test of high school students by the material cost of 1 yuan to 2 yuan; the volume of the geomagnetic universal electric meter can be decreased, and the diameter phi is smaller than 25 mm; the geomagnetic universal electric meter can made into a minityped electric meter for making a multi-function test pencil having the functions of a test pencil, a universal meter, and a compass; the geomagnetic universal electric meter is not easy to crash; when overload, the geomagnetic universal electric meter is not easy to burn out; the meter head is sensitive, and the full-load range of the milliampere grade is 5 milliampere; the geomagnetic universal electric meter is provided with the ac voltage grade of 1 volt for the experiments of alternating current.

Digital multimeter for comprehensive measurement of power system

Abstract: The utility model relates to a digital multi-meter for comprehensive measurement of the power system which is an electric meter used to measure the integrated electrical parameter, such as electric current, electric voltage, power-factor, etc., in the electric system. The utility model can be widely used for electric power plants, control centers, transformer stations, and other measuring. The digital multi-meter for comprehensive measurement of the power system is made into the installation type panel meter with digital switch. One digital multi-meter can replace a plurality of pointer type meter, and the displaying is visual, clear and centralized; the digital multi-meter can also be made into the portable meter. The utility model can export the analog sampling signal for measuring and controlling, and the digital coding signal. The digital coding signal can be matched with an automatic printing machine, a computer, etc., and proceed to the distance transmission. The digital multi-meter can be used to provide the ready condition for the achievement of the modernization management, the measurement and the control of the distribution room, and the distribution room with the electric system.

Constant power microbeam plasma arc welder

Abstract: The power supply of the similar kind of welders so far is not constant power source according to analysing the concept about of power supply. According to this invention, a special serial adjusting system with reciprocal devices and amplifiers of adjutable amplification is used, and indexes of performance of the system are modified, so as to make it a constant power source. The electronic switch circuit is also used, so as to make the welder perform the welding function with pulse constant power. In addition, the welder has electronic power meter for measuring welding power. Welded seams with good quality can be made by using the welder.

Solid state electricity meter

Abstract: In a solid state electricity meter, a display (16) consisting of a number of juxtaposed display elements provides, in a vector form, an indication of the direction and range of power flow in the line being measured. Circuitry for driving the vector display comprises a first memory storing a plurality of power measurement references and a second memory storing corresponding vector symbols. A microprocessor (50) compares each power measurement with the references stored in the first memory to determine the range of the power measurement and, in response, reads the corresponding vector symbol from the second memory to drive the display (16).

Automatic on-off switch for electric meter voltage coil

Abstract: The utility model discloses an automatic on-off switch for electric meter voltage coils, which is an electricity saving device, the utility model can automatically switch off the voltage coil of an electrical meter when the electrical meter is in no-load, and therefore, the electricity can be saved. When the electrical meter is provided with load, the utility model can automatically switch on the voltage coil of the electrical meter, so the electrical meter can restore power measuring.

Electronic electricity meter with automatic measuring range extension

Abstract: of EP01379421. An electronic electricity meter comprising a multiplier (1) for current and voltage, followed by a quantizer (2, 3) with a switchable conversion ratio and a counting device (4), and the current input of the multiplier being preceded by an input circuit (6) with a switchable conversion ratio, characterised in that the quantizer (2, 3) is followed by an analysing stage (5) for the clock pulse period of its output voltage, and that the analysing stage (5) controls the input circuit (6) and the switching input of the quantizer (2, 3) such that above a limit value of the clock pulse period the input signal of the current input of the multiplier (1) is increased and the conversion ratio of the quantizer (2, 3) raised to such an extent that the effect of the increase in the input signal is compensated.

A Method of Deriving Overall Accuracy for Single Phase Watthour Meters

Abstract: The ANSI Standard equation for overall accuracy places a small amount of emphasis on light load accuracy for watthour meters. Results from a recent load research study indicated a significant amount of energy is accumulated at lighter loads where watthour meter accuracy is poorer. Perhaps the standard equation for overall accuracy is a consensus of opinions prior to utilities performing load research studies. Although small inaccuracies of watthour meters at lighter loads may seem insignificant, they become large when applied to an entire meter population. ANSI C12.1-1982 may be interpreted to mean that 20% of all energy registration occurs at light load. The results of a load research study show that watthour meters spend a great deal of time at light loads. A method was developed to establish at which loads watthour meters register energy consumption. Watthour meters spent 85% of the time and registered more than 40% of the total energy for a one year period at light loads.