and can moves freely. • In electrodynamometer type wattmeter, moving coil works as pressure coil. • Hence moving coil is connected across the voltage and thus. Study of ammeter, voltmeter and wattmeter connections. • To investigate the errors .. an electrodynamometer for use as a wattmeter is shown in Fig. is kep. 5 Nov Electrodynamometer Wattmeter consists of two coils, pressure coil (PC) and current coil (CC). Pressure coil is connected across the circuit.
|Published (Last):||1 August 2017|
|PDF File Size:||7.63 Mb|
|ePub File Size:||8.88 Mb|
|Price:||Free* [*Free Regsitration Required]|
Submit Your Questions Here! Control System Out of two controlling systems i. If there is phase difference between voltage and electric current, then expression for instantaneous current through current coil can be written as As current through the pressure coil is very very small compared to the current through current coil hence current through the current coil can be considered as equal to total load current.
Scale There wattmeteer uniform scale which is used in these types of instrument as moving coil moves linearly over a range of electrodtnamometer degrees to 50 degrees on either side. Subscribe to our mailing list and get interesting stuff and updates to your email inbox.
One coil is fixed and another coil is moving. Transfer chute design using rocky software Posted 10 days ago. Consider the arrangement shown in figure 1 b. Now let the applied value of voltage across the pressure coil be Assuming the electrical resistance to the pressure coil be very high hence we can neglect reactance with respect to its resistance. Next Types leectrodynamometer Fossil Fuels. The deflection of the pointer of a dynamometer instrument is proportional to the current through the moving coil, but it is also proportional to the flux density of the magnetic field set up by the stationary coils.
The supply voltage applies to the moving coil. Hence the instantaneous value of torque can be written as Average value of deflecting torque can be obtained by integrating the instantaneous torque from limit 0 to T, where T is the time period of the cycle.
Electrodynamometer Wattmeter – Construction | Electrical Concepts
Following are the errors in the electrodynamometer type wattmeters: Electrodynamometer Wattmeter — Construction. Construction and Working Principle Advantages Errors. The voltage across the pressure coil of the circuit is given as. It uses for measuring the power of both the AC and DC circuits.
Electrodynamometer Type Wattmeter
Where, x is the angle. The working principle elevtrodynamometer the Electrodynamometer Wattmeter is very simple and easy. The dynamometer instrument can also be employed as a voltmeter or ammeter. Earlier these fixed coils are designed to carry the current of about amperes but now the modern wattmeter are designed to carry current of electrodybamometer 20 amperes in order to save power. Your email address will not be published.
But we know that. Stay ahead in your courses Sign UP now. This site uses Akismet to reduce spam. However, it is much more convenient to have an instrument that indicates power directly. Your email address will not be published. As a high value of series resistance is connected in series with the PC, therefore Dlectrodynamometer circuit can be assumed purely resistive.
Hence the current flows through the pressure coil is considered as the total load current. For electrodynamometr we connect the wattmeter to the circuit as shown in figure below. Posted 9 days ago.
There are two types of coils present in the electrodynamometer. It consists of following parts There are two types of coils present in the electrodynamometer. Moving coil is also called Pressure Coil or PC. The torque acts on the coils becomes. The fixed coil connects in series with the circuit whose power consumption use to be measured. So the expression for the torque can be written as: The following result hasbeen presented elcetrodynamometer Learn how your comment data is processed.
The pressure coil current in a low pf wattmeter may be as much as 10 times the value used for ordinary wattmeters. The fixed wattmetsr is divided into two equal parts and these are connected in series with the load, therefore the load current will flow through these coils.
Errors may be due connections.
Let I 1 and I 2 be the instantaneous values of currents in pressure and current coils respectively. Fixed Coil The fixed coil is divided into two equal parts and these are watteter in series with the load, therefore the load current will flow through these coils.
If the pressure coil is purely elecrodynamometer, then their current is in phase with the voltage. Then, when a current is passed through the moving coil, the moving coil and the meter pointer are deflected. Hence moving coil is connected across the voltage and thus the electric current flowing through this wattmwter is always proportional to the voltage.
Subscribe to our mailing list and get interesting stuff and updates to your email inbox. Consequently, its major application is as a wattmeter.