Single phase power measurement instruments are made up of rugged electronic instruments designed specifically for use in the harsh electrical environment common to many utility and industrial applications. Three phase ac amperage convert between single phase 120. These graphics below shows the above idea in a very simple way. Pic18f87j72 singlephase energy meter calibration users. Power factor meters electrodynamometer type power factor. The total energy is the sum of the reading of both the elements. Power and energy measurements encyclopedia of life. Laureate ac power factor meter ac phase angle meter. Iskra power factor meters are intended for measurement of power factorb cos.
Calculator1 input the system linetoneutral voltage, line current, and power factor angle degrees into calculator1 to compute singlephase reactive power, real power, and total power as well as the power factor. Its adverse effects include degradation of system voltage waveforms, reduction of power factor, etc. An adjustable copper shading rings are provided on the central limb of the shunt magnet to make the phase angle displacement between magnetic field set up by shunt magnet and supply voltage is approximately 90 degree the copper shading bands are also called the power factor compensator or compensating loop. Ii power and energy measurements arnaldo brandolini and alessandro gandelli encyclopedia of life support systems eolss where p, v, i are instantaneous power, voltage, and current, respectively. The meter which is used for measuring the energy utilises by the electric load is known as the energy meter. Unesco eolss sample chapters electrical engineering vol. All power measurements are taken in the digital domain.
Connection diagram false phase sequence leads to error power factor meter frequency meter ppd96 transducer type pad96 single phase power factor meter ppd9612 external pt62m12 three phase power factor meter balance ppbd96n33 three phase power factor meter unbalanced ppd96n33 three phase 4 wire unbalanced power factor meter. Singlephase induction kilowatt hour meter construction. Two identical pressure coils a and b pivoted on a spindle constitute the moving system. Power wiring color codes color codes used in power wiring. The energy is the total power consumed and utilised by the load at a particular interval of time. This article is only focused about its constructional features and its working. Implementation of a singlephase electronic watthour meter using msp430afe2xx rev. Power factor inductive load inductive loads and power factors for electrical threephase motors. It uses ad7755, a singlephase energy measurement ic to acquire and process the input voltage and current parameters. Implementation of a singlephase electronic watthour. Number meter elements type of circuit of lines required single phase 2 1 3phase, 3wire, delta 3 2 3phase, 4wire wye 4 3.
The power factor is indirectly determined by measuring the phase angle between current and. One single phase energy meter, one single phase load, stop watch and connecting wires. Working of single phase induction type energy meter the basic working of single phase induction type energy meter is only focused on two mechanisms. The measurement of energy is accomplished by means of a voltagefrequency converter connected downstream from the power meter. Product leaflet single phase electricity meters b21 eq. But as we need to sample the voltage and current to get the power, hence it need to be calculated by using this formula.
In a single phase meter measurement, the power is being measured by using the instantaneous power which is pt vt it. Electronic measurement power factor meter slideshare. The meter which is used for measuring the power of three phase supply is known as the three phase energy meter. Singlephase electric meter with isolated energy measurement. Introduction the generation and transmission of electricity is commonly accomplished by means of three phase circuits. The power factor of an ac power system is the ratio of real power in watts w divided by apparent power in voltamperes va. In power transmission system and distribution system we measure power factor at every station and electrical substation using these power factor meters. A wide variety of single phase power factor meter options are available to you, such as phase, display type.
This meter can be mounted on panels of any kind of materials. Why we do not directly calculate power factor in an ac circuit just by dividing the power with product of current and voltage because these readings can. Coils m and m 1 are mounted on a common shaft, which is free to move without restraint or. The basic principle of this instrument is the same as that of the singlephase dynamometer type power factor meter. The following calculators compute reactive power in a singlephase system based on kw and kva or voltage, current, and power factor. The meter is designed to offer reliable energy measurement in single phase. Ev battery charger employing a threephase twolevel active power filter and. Electric components of a utility distribution system are designed on a kva basis. The indication on each meter is the power being delivered by the line to which the meter is connected. It is used in domestic and industrial ac circuit for measuring the power consumption. Single phase power factor meter home energy monitoring instruments single phase power factor meter products code. Before we introduce various types of power factor meters it is very essential to understand what are the needs of power factor meter.
Low voltage products power factor improvement application. The three phase meter is constructed by connecting the two single phase meter through the shaft. Simple capacitive power supply for the msp430 energy meter. The power factor is the cosine of the angle between the voltage and current. Measurement of power singlephase threewire system split phase the voltage and current detected by the meters are the voltage and current applied directly to the load. A power factor of less than one indicates the voltage and current are not in phase. Rms, fundamental, and harmonic currents and voltages are also computed for each phase. Calculating and measuring power in three phase circuits 1.
Below are the the connections diagrams for installation of a singlephase 3phase, 4 wire kwh meter digital or analog energy meter from the supply to the main distribution board in home. The measurement of single phase power and power factors 6. It is a singlephase meter for direct metering installations with a capacity of up to 100 amperes. Pic18f87j72 singlephase energy meter calibration users guide 2011 microchip technology inc. Figure 1 provides a block diagram of the 78m6631 ic. The function of recording or registering mechanism is to record continuously a number on the dial which is proportional to the revolutions made by the moving system. The power factor meter determines the types of load using on the line, and it also calculates the losses occur on it. Analysis and control of a threephase, unity power factor y rectifier. Overview of single phase induction type energy meter.
Power factor range zero lag unity zero lead frequency 50 hz. About 0% of these are power distribution equipment, 39% are energy meters, and 50% are power meters. Power factor is the ratio of true power and inductive power. The 1500w singlephase acdc converter with power factor correction pfc is designed to reduce harmonic currents and.
Technical specifications for single phase static meter the equipment covered by these broad specifications shall conform to the requirements stated in latest editions of relevant indian iec standards and regulations. The method of connection of this type of power factor meter, in a 3 f circuit, is shown in figure 14. The series electromagnet is energized by a coil, known as current coil which is connected in series with the load so that it carry the load current. Single phase electrodynamometer power factor meter.
Energy meter is an instrument which measures electrical energy. What is the nature of power factor in single phase. Pdf a single phase microcontroller based energy meter. Simpson amik 200 three phase digital energy and power. Metallurgical contentpower factor meter methodvoltmeter, ammeter, wattmeter methodtwo singlephase watthour meters methodthreephase wattmeter methodwatthour meter, splitcore ammeter methodwatthour meter, reactive kva hour meter methodpower factor of typical ac loadsunity or near unity power factorincandescent lamps and resistor heaters. Product leaflet single phase electricity meters b21 eq meters in silver version from abb the compact and versatile eq meters b21 in silver version is a single phase meter with full four quadrants measuring meaning both activereactive energy measurements, importexport of energy and tariff handling. The individual pulses are then summated through the use of an electromechanical meter, and are made available at a pulse output as well. Although electrical service to residential buildings in the usa are exclusively by single phase circuits, electrical. In threephase network assymetrical loaded is demanded to use three meters. The flux produced by this magnet is proportional to, and in phase. The two stationary coils, s and s 1, are connected in series in phase b. Hi there, i have a circuit consisting of four single phase induction motors. Mechanism of rotation of an aluminum disc which is made to rotate at a speed proportional to the power. Institute of intelligent power electronics publications publication 6 topological issues in singlephase power factor correction vlad grigore dissertation for the degree of doctor of science in technology to be presented with due permission for public examination and debate in auditorium s4 at helsinki.
Measurement of active power, p, by means of the wattmeter, and apparent power, by. In electrical engineering, the power factor of an ac electrical power system is defined as the ratio of the real power absorbed by the load to the apparent power flowing in the circuit, and is a dimensionless number in the closed interval of. The principle of working and construction of induction type meter is very simple and easy to understand thats why these are widely used in measuring energy in domestic as well as industrial world. Pressure coil a has a noninductive resistance r connected in series with it, and coil b has a highly inductive choke coil l connected in series with it. To study the construction and working of single phase energy meter and to find out energy consumed in 30 minutes.
Power in a nonlinear system driven by a sinusoidal voltage waveform 4. Single phase energy meter single phase induction type energy meter is also popularly known as watthour meter. The msp430f663x, the host processor in this twochip architecture, has a powerful 20mhz cpu with an. This application report has the complete metrology source code. A dynamometer type threephase power factor meter gives correct readings only when the load is balanced. The power factor meter measures the power factor of a transmission system. Facilities instructions, standards, and techniques volume 310. A singlephase meter is used in alternating current systems. Visiontek 36sm single phase static electronic energy meter is designed to meter residential and small commercial energy consumers in distribution networks. Induction type energy meter essentially consists of following components.
Now rotate the rotor of phase shifting transformer so that the working power factor p. Veritas approval certificate for eq, yq, bq, wq and cq series pdf 411 kb. These power measurement instruments are ideally suited to applications where reliable, precise measurements are required, but where. The voltage and currents of the power line are rated down to signal level using transducers like voltage and current transformers and given to that ic as shown in the figure. Design easily downgrades to fit normal singlephase energy metering. The energy register shall be of 6 digits, cyclometer type capable of registering. Calculating and measuring power in three phase circuits. Single phase energy meter working of single phase induction. Power in a linear system driven by a periodic voltage waveform 3. You can easily find electric power in watts by using the following power formulas in electric circuits. Single phase power factor meter pdf lh60 single phase power meter reference design, rev. The 2 elementtype meter is designed to operate from current in two of the three phases and the potential be tween the two phases, as shown in figures 10 and 11. I need to work out how to correct the power factor to 0.
Singlephase ami smart meter for meter code 0510 the u1200 electronic meter is western powers trial meter as part of a trial of the use of smart meters, also known as advanced metering infrastructure ami. In all induction meters we have two fluxes which are produced by two different alternating currents on. Power factor meter fa39 type is destined to measure the phase angle difference between the voltage and the current in 1phase or 3phase a. Calibration and testing of singlephase energy meter.
Power formulas in dc, ac single phase and ac three phase circuits. Therefore, 10% more current is required to handle the same load. The copper shading bands are also called the power factor compensator or compensating loop. Back to basic, below are the simple power formulas for single phase ac circuit, three phase ac circuits and dc circuits. Nepsi reactive power in a 1phase system calculator. A direct reading power factor meter can be made with a moving coil meter of. Power factor correction single phase induction motors. A wide variety of single phase digital power meter options are available to you, such as phase, display type. The pfq power factor meter measures cos phi with a moving coil movement and an electronic transducer.
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