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How would you measure power factor of the balanced three phase load by two wattmeter method?
Wiki User
∙ 8y ago
Yes. The wattmeter's current coil will have to be connected into one of the line conductors, and its voltage coil between that same line conductor and the neutral point of the load.
Connected this way, the wattmeter's voltage coil is measuring one of the three phase voltages (line-to-neutral voltage) while its current coil is measuring the corresponding phase current (for a 4-wire system, the phase current = line current). The power factor (cosine of the phase angle) is accounted for automatically within the wattmeter.
So the wattmeter will measure the true power (in watts) of one phase.
The total power, therefore, will be 3x the wattmeter reading -providing, of course, that the load is balanced (i.e. each phase is identical). WebRep
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Wiki User
∙ 9y ago
Wiki User
∙ 8y agoThe two wattmeters would indicate the total power, and then an ammeter would have to be used on one of the phases (assuming balance) to measure the current. The power factor can be calculated from that data.
Wiki User
∙ 6y agoYes. It is one proven method to measure power in a three phase system.
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How you measure power factor in three phase load by two wattmeter method?
First of all, you can only measure power factor of a three-phase load, provided that it is balanced load. The power factor can then be found by determining the cosine of the phase angle, using the following equation:tan (phase angle) = 1.732 ((P2-P1)/(P2+P1))...where P1 and P2 are the readings of the two wattmeters.
How would you measure power using three watt meter and one watt meter for balanced and unbalanced loads?
The 'one wattmeter method' can only be used for balanced, wye-connected, loads where the load's neutral point is accessible. The wattmeter's current coil is inserted into any line conductor, and the voltage coil is connected between the same line and the neutral point. The wattmeter reading indicates the power of one phase, so the total power is three times the wattmeter reading.To measure the total power of a balanced or unbalanced wye- or delta-connected load, it is only necessary to use twowattmeters -this is called the 'two wattmeter method'. In this case, the current coils of each wattmeter are inserted into any two line conductors, and the voltage coils are connected between the two line conductors and the third line conductor. The sum of the two wattmeter readings will indicate the total power of the load.
Will the two-wattmeter method work for all three-phase loads eg unbalanced loads inductive loads capacitive loads and delta-connected loads?
Blondel's Theorem tells us that, to measure the total power of a three-phase load (balanced or unbalanced), we can use one less wattmeter than there are conductors supplying that load.So the two-wattmeter method will work for anythree-phase load, provided there are only threeconductors supplying that load, e.g. three-wire delta or three-wire star (wye).Bear in mind that wattmeter's read true power (expressed in watts) and ignores the reactive power of inductors and capacitors.
What is the three ammeter method?
I am assuming that you really want to use ammeters to measure power in a balanced 3 phase system. (hope you are not meaning 3 watt meter method) Power in Watt in a three phase system is equal to 1.73 x line voltage x line current x power factor. You need to know line voltage, power factor also in addition to current to compute the power. If the system is balanced then actually you do not need to connect ammeters in all three lines. One ammeter reading will do.
Explain the Two wattmeter method of power measurement in a 3 phase circuit?
A single wattmeter can measure power due to one phase only. But circuit arrangements , popularly called: 1) 2-wattmeter method (requiring two wattmeters) 2)3-wattmeter method (requiring 3 wattmeters) can be used for measuring power inn 3-phase circuit. The details of these method can be found in any standard book on electrical engineering.
Is it possible to measure power factor of the balanced three-phase load by two-wattmeter method?
yes.
How you measure power factor in three phase load by two wattmeter method?
First of all, you can only measure power factor of a three-phase load, provided that it is balanced load. The power factor can then be found by determining the cosine of the phase angle, using the following equation:tan (phase angle) = 1.732 ((P2-P1)/(P2+P1))...where P1 and P2 are the readings of the two wattmeters.
How would you measure power using three watt meter and one watt meter for balanced and unbalanced loads?
The 'one wattmeter method' can only be used for balanced, wye-connected, loads where the load's neutral point is accessible. The wattmeter's current coil is inserted into any line conductor, and the voltage coil is connected between the same line and the neutral point. The wattmeter reading indicates the power of one phase, so the total power is three times the wattmeter reading.To measure the total power of a balanced or unbalanced wye- or delta-connected load, it is only necessary to use twowattmeters -this is called the 'two wattmeter method'. In this case, the current coils of each wattmeter are inserted into any two line conductors, and the voltage coils are connected between the two line conductors and the third line conductor. The sum of the two wattmeter readings will indicate the total power of the load.
Is there any difference in values between the two wattmeter method and three wattmeter method if you apply these two methods in same load?
Blondel's Theorem states that you can have one less wattmeter than there are conductors supplying a balanced or unbalanced load. In either case, the sum of the wattmeter readings will give you the total power of the load.
Can reactive power measure by 2 wattmeter method?
Active volts amperes are measured by 2 wattmeter methods. A wattmeter will measure active power and not reactive power. Electrical engineering is a promising career for anyone who likes to generate power.
What are the advantages of two-wattmeter method over other methods and it is applicable to which type of system?
(a) Access to the star point is not required. (b) The power dissipated in both balanced and unbalanced loads is obtained, without any modifi cation to the connections. (c) For balanced loads, the power factor may be determined.
Write down the advantage of 2-wattmeter method instead of 3-wattmeter method for measuring ac power?
It's cheaper.
Will the two-wattmeter method work for all three-phase loads eg unbalanced loads inductive loads capacitive loads and delta-connected loads?
Blondel's Theorem tells us that, to measure the total power of a three-phase load (balanced or unbalanced), we can use one less wattmeter than there are conductors supplying that load.So the two-wattmeter method will work for anythree-phase load, provided there are only threeconductors supplying that load, e.g. three-wire delta or three-wire star (wye).Bear in mind that wattmeter's read true power (expressed in watts) and ignores the reactive power of inductors and capacitors.
Why do you use two phase watt meter?
You may be thinking of the 'two-wattmeter method' for measuring three-phase power?As a rule, it's always possible to use one less wattmeter than the number of conductors supplying a three-phase load to measure the power of that load. So, for a three-phase, three-wire, system, two wattmeters may be used to measure the total active power of the load -regardless of whether the load is balanced or unbalanced. The algebraic sum of the two wattmeter readings will give the total power.
Why is one watt meter method of power measurement not applicable to unbalanced circuits?
The one wattmeter method will only measure the power of the phase to which it is connected. So, by reconnecting it to measure each phase separately, you can measure the power in each phase in turn, and add them up to give you the total power.
Method of synchronization of an alternator?
there are many ways of synchronization.2.1 Synchronizing lamps2.2 Synchroscope2.3 Synchronizing relaysalso there are wattmeter method and lamp method
What is the effect of variation of power factor on readings of two wave meters used in 3 phase power mesurements?
I assume that you mean 'watt meters', and not 'wave meters', in this question, and that you are referring to the 'two wattmeter method' of measuring the power of a three-phase load.Variations in power-factor will cause the ratio of the two wattmeter readings to vary, but the sum* of those readings will always indicate the total power of the load. Providing the load is balanced, you can use the ratio of the two wattmeter readings (P1 and P2) to determine its power factor, based on the following equation:phase angle = tan-1 {1.73[(P2 - P1) / (P2 + P1)]}Where power factor is then the cosine of the phase angle determined by this equation.[*If one or other of the wattmeters is reading 'downscale' -backwards- then it will be necessary to reverse the connection to that instrument's voltage or current coil.]
