The wattmeter is an instrument for measuring the electric power or the supply rate of electrical energy in watts of any given circuit. Electrodynamic wattmeter article about electrodynamic. Dec 21, 2019 in electrodynamometer type wattmeter, moving coil works as pressure coil. Electrodynamometer type instruments free download as powerpoint presentation.
Measurement of threephase power with the 2wattmeter. Dynamometer type wattmeter electrical technology study buddy. Before we study the internal construction of electrodynamometer wattmeter, it very essential to know the principle of working of electrodynamometer type wattmeter. Thus circuit voltage is impressed across the pc and cc carries the circuit current. Electrodynamic instrument article about electrodynamic. However, unlike the darsonval or weston movement, another stationary.
Dynamometer type instrument,electrical engineering. It consists of a measuring transducer, which converts the quantity being measured into an alternating or direct current, and a measuring mechanism of an electrodynamic system figure 1. For example, in using an electrodynamic wattmeter on direct current, two readings are taken, the direction of. Electrodynamometer wattmeters a media to get all datas. A special meter movement designed especially for power measurement is called the dynamometer movement, and is similar to a darsonval or weston movement in that a lightweight coil of wire is attached to the pointer mechanism. Apr 24, 2018 an electrodynamometer wattmeter have two types of coils. Dynamometer type wattmeter construction and working principle. Nov 03, 2019 the working principle of the electrodynamometer wattmeter is very simple disturbs the main magnetic field of the electrodynamic wattmeter. The traditional form of wattmeter is called as dynamometer wattmeter. Now let us look at constructional details of electrodynamometer. Electrodynamometer type wattmeter electrical study app by. A special meter movement designed especially for power measurement is called the dynamometer movement, and is similar to a darsonval or weston movement in that a lightweight coil of wire is. Classification, absolute and secondary instruments, indicating instruments, control, balancing and damping, constructional details, characteristics, errors in measurement, ammeters, voltmeters.
Electrodynamometer wattmeters these instruments are similar in design and construction to electrodynamometer type ammeters and voltmeters. Measurement of threephase power with the 2wattmeter method. Dynamometer type wattmeter working your electrical guide. Model 44ap wattmeter with optional tc44 carrying case, rf loads optional accessories 4. A transfer instrument is one which is calibrated with a d. Aug 22, 2018 electrodynamic type instruments are similar to the pmmctype elements except that the an electrodynamometer for use as a wattmeter is shown in fig. 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.
The working principle of the electrodynamometer wattmeter is very simple disturbs the main magnetic field of the electrodynamic wattmeter. 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. In open circuit test the secondary winding of transformer is kept open. Electrodynamometer wattmeter are often used for the measurement of power consumption. So electrodynammeter expression for the torque can be written as. Construction and working principle of electrodynamometer type wattmeter. The two coils are connected in different circuits for measurement of power. 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. Sep 04, 2019 there is a requirement of low power factor meter because, the usage of ordinary electrodynamometer wattmeter to measure power factor of a low pf load gives inaccurate results. Jan 09, 2020 electrodynamometer wattmeter pdf electrodynamometer wattmeter consists of two coils, pressure coil pc and current coil cc. Lpf wattmeter pdf the instrument that measures the low value of power factor accurately is known as the low power factor wattmeter lpfw. Dynamometer type wattmeter construction and working.
In electrodynamometer type wattmeter, moving coil works as pressure coil. Electrodynamometer wattmeter construction electrical concepts. Two wattmeter method 3 phase power measurement duration. 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. Therefore this fixed coil is often called current coil cc. 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. For example, in using an electrodynamic wattmeter on direct current, two readings are taken, the direction of current flow through the instrument being reversed. The pressure coil can also be tapped to change the meters range. The traditional analog wattmeter is an electrodynamic instrument.
View electrodynamometer ppts online, safely and virus free. The instrument whose working depends on the reaction between the magnetic field of moving and fixed coils is known as the electrodynamometer wattmeter. Wattmeter are illustrated in figure 21, and the functions of these elements are described in table 21. Find out information about electrodynamic wattmeter. Electrodynamic type instruments are similar to the pmmctype elements except that the an electrodynamometer for use as a wattmeter is shown in fig. 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.
This is a online courseware website for sns college students through this website student can access their materials. Consult the current price list or our website for current pricing. Electrodynamometer type wattmeter in general, a watt meter is used to measure the wattmster power of a circuit, or sometime it also measures the rate of energy transferred from one circuit to another circuit. 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. Jan 22, 2020 electrodynamometer type instruments pdf the electrodynamometer type instrument is a transfer instrument. Hence moving coil is connected across the voltage and. Power in an electric circuit is the product multiplication of voltage and current, so any meter designed to measure power must account for both of these variables electrodynamometer movement. Nov 15, 2018 electrodynamometer wattmeter pdf and can moves freely. Electrodynamometer wattmeter pdf electrodynamometer wattmeter consists of two coils, pressure coil pc and current coil cc. The dynamometer wattmeter works on the motor principle.
The scale of the wattmeter illustrated in figure 2 is read directly only when the range switches are set to 1 a and 120 v. Moving coil is connected across the supply voltage. We know that instantaneous torque in electrodynamic type instruments is directly. The fixed coil is connected in series to the circuit whose power consumption is to be calculated. These instruments are similar in design and construction to electrodynamometer type ammeters and voltmeters. Construction of electrodynamometer wattmeter fixed coils the fixed coils carry the current of the circuit. It consists of following parts there are two types of coils present in the electrodynamometer. Moving coil moves the pointer with the help of spring control instrument. Dynamometer type wattmeter electrical technology youtube.
Dynamometer type wattmeter works on very simple principle and this principle can be stated as when any electric current carrying conductor is placed inside a magnetic field, it experiences a mechanical force and due this mechanical. 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. Jul 18, 2019 lpf wattmeter pdf the instrument that measures the low value of power factor accurately is known as the low power factor wattmeter lpfw. 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. Electrodynamic instrument a measuring instrument whose operation is based on. This device is available in a purely electronic form too which is known as digital wattmeter. There is a requirement of low power factor meter because, the usage of ordinary electrodynamometer wattmeter to measure power factor of a low. Electromagnetic wattmeters are used for measurement of utility frequency and audio frequency power. Electrodynamometer type wattmeter working principle. We will discuss electrodynamometer type wattmeter working principle and its construction. Electrodynamometer definition is an ammeter or galvanometer in which the torque due to the reaction between two coils in series with each other is balanced by a spiral spring.
Pressure coil is connected across the circuit whose power is to be measured and current coil is connected in series. Electrodynamometer type instruments download as powerpoint presentation. The fixed coils or field coils are connected in series with the load and so carry the. Since the moving coil carries a current proportional to the voltage, it is called the pressure coil or voltage coil or simply called p. These coils are called the electric current coils of electrodynamometer type wattmeter.
Apr 08, 2018 electrodynamometer wattmeter consists of two coils, pressure coil pc and current coil cc. Dynamometer type wattmeter working principle electrodynamometer. In order to derive these expressions let us consider the circuit diagram given below. The fixed coils or field coils arc connected in series with the load and so carry the current in the circuit. As shown in the above figure, the wattmeter has two sets of coils. Electrodynamometer type wattmeter construction and working. It is important to avoid excessive current flow in the voltage and current coils of a wattmeter. Now let us look at constructional details of electrodynamometer type wattmeter. It uses for measuring the power of both the ac and dc circuits. An electrodynamometer wattmeter have two types of coils.
Before we study the internal construction of electrodynamometer type wattmeter, it is essential to know the working principle of electrodynamometer type wattmeter. When power is consumed, such as in a light bulb a current flows through the conductor. An electrodynamic instrument connected as a wattmeter, with the main current flowing through the fixed coil, and a small current proportional to the voltage. Key item description 1 carry strap for carrying or hanging the instrument.
An electrodynamic instrument connected as a wattmeter, with the main current flowing through the fixed coil, and a small current proportional to the voltage flowing through the movable coil. If two coils are connected such hence an electrodynamic instrument, when connected as shown in. Electrodynamometer type wattmeter when a moving coil that is free to rotate is kept under the influence of a current carrying conductor, then automatically a mechanical force will be applied to the moving coil, and this force will make a little deflection of the moving coil. Electrodynamometer type instruments alternating current.
Electrodynamometer wattmeter consists of two coils, pressure coil pc and current coil cc. Wattmeter design dc metering circuits electronics textbook. Electrodynamometer definition of electrodynamometer by. Electrodynamometer type instruments pdf the electrodynamometer type instrument is a transfer instrument.
Also, on analog wattmeters, the potential coil carries a needle that moves over a scale to indicate. Nov 29, 2014 the traditional form of wattmeter is called as dynamometer wattmeter. Sep 21, 2019 the working principle of the electrodynamometer wattmeter is very simple disturbs the main magnetic field of the electrodynamic wattmeter. Electrodynamometer wattmeter pdf and can moves freely. Electrodynamo type wattmeter electrodynamometer type wattmeter when a moving coil that is free to rotate is kept under the influence of a current carrying conductor, then automatically a mechanical force will be applied to the moving coil, and this force will make a little deflection of the moving coil. Electrodynamometer type wattmeter electrical study app.