The instrument whose working depends on the reaction between the magnetic field of moving and fixed coils is known as the electrodynamo meter wattmeter. The transition from a negative to a positive value occurs. Digital wattmeter english mainpage vis dansk oversat side new software available 28 okt 2008. Introduction describes the features of the 43 wattmeter, lists equipment supplied and optional equipment, and provides powerup instructions. Jun 15, 2018 working principle of voltmeter the main principle of voltmeter is that it must be connected in parallel in which we want to measure the voltage. Due to this the sizes of earlier wattmeter were large. Pdf on oct 1, 2016, slami saadi and others published. End applications like commercial, industrial and domestic purpose.
Types of energy meters and their working principles. The wattmeter measures the electricity used in terms of the number of watts used. Bird model 43 wattmeter ii safety symbols this symbol appears on the equipment indicating there is important information in the instruction manual regarding that particular area. As shown in the above figure, the wattmeter has two sets of coils. As evident from the name, a wattmeter is used for measuring the total power across any circuit. Dynamometer type wattmeter works on very simple principle and this principle can be stated as when any current carrying conductor is placed inside a magnetic field, it experiences a mechanical force and due to this. Before we study the internal construction of electrodynamometer wattmeter, it very essential to know the principle of working of electrodynamometer type. Dynamometer type wattmeter construction and working principle. A wattmeter is a tool used to measure the amount of electricity being used. For example, in using an electrodynamic wattmeter on direct current, two readings are taken, the direction of current flow through the instrument being reversed. Nov 29, 2014 the traditional form of wattmeter is called as dynamometer wattmeter. Electrodynamometer type wattmeter working principle. Rf directional thruline wattmeter model 43 repeater builder. It simultaneously measures the voltage and current values and.
The two coils are connected in different circuits for measurement of power. The current and voltage of the fixed and moving coil generate the two magnetic fields. Electrodynamometer type, induction type, single phase and three phase wattmeter. Bird model 43 wattmeter ii resuscitation personnel working with or near high voltages should be familiar with modern methods of resuscitation. The wattmeter is an instrument for measuring the electric power or the supply rate of electrical energy in watts of any given circuit. Safety symbols this symbol appears on the equipment indicating there is important information in the instruction manual regarding that particular area. If two coils are connected such that, current proportional to the load voltage, flows through one coil and current proportional to the load current, flows through another coil, the meter can be calibrated directly in watts. The rf line section is precision machined to provide the best possible impedance match to the transmission line under test. Electrodynamometer wattmeter are often used for the measurement of power consumption. Simultaneously, watt readings using a standard commercially available analogue wattmeter were also taken.
Pdf implementation of a digital wattmeter on fpga researchgate. It consists of following parts there are two types of coils present in the electrodynamometer. View and download bird thruline 4304a operation manual online. Bird model 43 wattmeter ii resuscitation personnel working with or near high voltages should be. Classification, absolute and secondary instruments, indicating instruments. The dynamometer wattmeter works on the motor principle. Oct 22, 2019 the page covers the basic working principle and constructional features of dynamometer type wattmeter. It uses for measuring the power of both the ac and dc circuits. At zero power factor, corresponding to a purely reactive load, both wattmeters will again have the same wattage indication but with the opposite signs, so that their algebraic sum will yield zero power absorbed, as it should. Now let us look at constructional details of electrodynamometer type wattmeter. A wattmeter does a complex job, measuring the power flowing through an electrical circuit. Design and hardware implementation of a digital wattmeter. The traditional analog wattmeter is an electrodynamic instrument.
Their working depends on the theory that the current carrying conductor placed in a magnetic field experiences a mechanical force. Be sure transmission line is terminated into a load or antenna. Given the two wattmeter readings from the two wattmeter method used on a threephase balanced load, it is possible to find the tangent of the phase impedance angle as times the ratio of the difference between the two wattmeter readings and their sum, based on equation 4. Construction and working principle of electrodynamometer type wattmeter. The device consists of a pair of fixed coils, known as current coils, and a movable coil known as the potential coil the current coils are connected in series with the circuit, while the potential coil is connected in parallel. A simple wattmeter method of measuring power involves two corrections.
This lets you remove the line section from the wattmeter housing for custom installation an d still make measurements. Wattmeters these instruments are similar in design and construction to electrodynamometer type ammeters and voltmeters. Personnel working with or near high voltages should be familiar with modern methods of resuscitation. Dynamometer type wattmeter construction and working.
Therefore this fixed coil is often called current coil or simply cc. The low power factor meter is used for measuring the power of the highly inductive circuit. Their working depends on the theory that the current carrying conductor. The page covers the basic working principle and constructional features of dynamometer type wattmeter. Wattmeter working principle construction types of wattmeter.
In this work, we present a design of a digital wattmeter pattern, implemented on a. Moving coil moves the pointer with the help of spring control instrument. Parallel connection is used because a voltmeter is constructed in such a way that it has a very high value of resistance. Utilities are one of the electrical departments, which install these instruments at every place like homes, industries, organizations, commercial buildings to charge for the electricity consumption by loads such as lights, fans, refrigerator, and other home appliances. The fixed coils or field coils are connected in series with the load and so carry.
Jun 08, 2019 before we study the internal construction of electrodynamometer type wattmeter, it is essential to know the working principle of electrodynamometer type wattmeter dynamometer type wattmeter works on very simple principle and this principle can be stated as when any current carrying conductor is placed inside a magnetic field, it experiences a mechanical force and due to this mechanical force. This device is available in a purely electronic form too which is known as digital wattmeter. These instruments are similar in design and construction to electrodynamometer type ammeters and voltmeters. The current coils are connected in series with the circuit, while the potential coil is connected in parallel. Electromagnetic wattmeters are used for measurement of utility frequency and audio frequency power. Measurement of threephase power with the 2wattmeter. So it is a measuring instrument which measures the potential difference between the two points working principle of voltmeter. Digital wattmeter with ad8307, pic16f876, lcd display. The fixed coils or field coils are connected in series with the load and so carry the. Working principle of voltmeter and types of voltmeter. The instrument that measures the low value of power factor accurately is known as the low power factor wattmeter lpfw.
For line to line voltages of 415v, phase current of 5a, phase angles of 80 capacitive. Types of energy meters and their working principles elprocus. Dynamometer type wattmeter works on very simple principle and this principle can be stated as when any current carrying conductor is placed inside a magnetic field, it experiences a mechanical force and due to this mechanical force. The working principle of the electrodynamometer wattmeter is very simple disturbs the main magnetic field of the electrodynamic wattmeter. Energy meter or watthour meter is an electrical instrument that measures the amount of electrical energy used by the consumers. Feb 20, 2018 in this video you will learn about how a wattmeter workand its construction. Do not open the instrument safety symbols warning notes call attention to a procedure, which if not correctly performed, could result in personal injury. Do not put fingers or other objects into the plugin element socket while rf power is applied. Given the two wattmeter readings from the twowattmeter method used on a threephase balanced load, it is possible to find the tangent of the phase impedance angle as times the ratio of the difference between the two wattmeter readings and their sum, based on equation 4. As shown in figure 318, it consists of a pair of fixed coils, known as current coils, and a moving coil, called the voltage potential coil.
The main cpu board is mounted directly on the display. In this post we are going to understand how wattmeter works. Caution for low reflection measurements, do not rotate the reflected power element to read forward power. The main principle of voltmeter is that it must be connected in parallel in which we want to measure the voltage. Also, on analog wattmeters, the potential coil carries a needle that moves over a scale to indicate. Electrodynamometer type wattmeter construction and working. Wattmeter is an electric instrument which is used to measure the electric power of various electric circuits. Theory of operation describes how the 43 wattmeter works and installation describes how to set up and prepare the 43 wattmeter for use. It also shows the derivation for deflecting torque.
The threewire, three wattmeter connection has the advantages of indicating the power in each individual phase not possible in the two wattmeter connection and phase to neutral voltages. First, for the power expended upon the fixed coil of the wattmeter. Wattmeter definition is an instrument for measuring electric power in watts. Wattmeter definition of wattmeter by merriamwebster. Dynamometer type wattmeter working your electrical guide. Now the reason is very obvious of using two fixed coils instead of one, so that it can be constructed to carry considerable amount of electric current. Dynamometer wattmeter working principle,construction. The three main types are electrodynamic, electronic and digital. It is also used in the resistive circuit which has a power factor range from 0. When working with rf powers of 200 watts or more, the potential of the center conductor of the line section will be over 100 volts. Before we study the internal construction of electrodynamometer type wattmeter, it is essential to know the working principle of electrodynamometer type wattmeter. Wattmeter electric power is measured by means of a wattmeter. Power factor meter working principle the basic working principle of power factor meter is similar to that of dynamometer type wattmeter i. The wattmeter software source code files can be downloaded from the free downloads section of the elektor electronics website.
A wattmeter is an instrument used to measure electrical power consumed i. Dynamometer type wattmeter and its deflecting torque. The threewire, threewattmeter connection has the advantages of indicating the power in each individual phase not possible in the twowattmeter connection and phase to neutral voltages. Thruline 4304a measuring instruments pdf manual download. In these wattmeters, the field produced by the currentcarrying moving coil tries to come in line with the field produced by the currentcarrying fixed coil, and a deflecting torque is exerted on the moving system. Now let us see the construction and working of hall effect multiplier. Number of wattmeters required in a singlephase system there are just two wires. Hall effect multiplier is also used where the multiplication of signals over a wide range of amplitudes is performed.
The electricity supply connection may be either single phase or three. Construction and working principle advantages errors. For example, in using an electrodynamic wattmeter on direct current, two readings are taken, the direction of. When plugin element is removed from the rf line socket, the line section center conductor is exposed. Hall effect multiplier construction, working principle. Do not open the instrument safety symbols warning notes call attention to a procedure, which if. The input board is a small pcb mounted directly on the connector. Bird model 43 wattmeter personnel working with or near high voltages should be familiar with modern methods of resuscitation. On this page you can read or download disadvantages of a wattmeter in pdf format.
Electrodynamic wattmeters are a design that goes back to the early 20th century. It simultaneously measures the voltage and current values and multiplies them to give power in watts. We have used several lamps having watt ratings of 40, 60 and 100watt as loads and measured real power dissipated at those loads using our designed digital wattmeter. Do not touch the center conductor while rf power is on. The fixed coils or field coils arc connected in series with the load and so carry the current in the circuit. Dec 21, 2019 the working principle of the electrodynamometer wattmeter is very simple and easy. This mechanical force deflects the pointer which is mounted on the calibrated scale. Bird model 43 wattmeter 2 a shielded cable connects the rf line section to the rest of the wattmeter. Technical aspects like single phases, three phases, high tension ht, low tension lt and accuracy class materials. Measurement of threephase power with the 2wattmeter method. Apr 26, 2019 electrodynamometer wattmeter are often used for the measurement of power consumption. Utilities are one of the electrical departments, which install these instruments at every place like homes. When a current carrying conductor is placed in a magnetic field, a transverse effect is noted.
1185 270 122 824 1433 292 1621 1343 910 874 544 1360 1139 867 196 227 489 1581 1142 710 559 936 321 1415 1183 1291 102 923 903 1445 606 1617 881 791 1586 300 1412 964 119 982 1141 1184 282 916 895 211 564