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A wattmeter is designed so that it measures the supply voltage and the in-phase component of the load current. The product of these two quantities is the true power of the load.

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What instrument can you use to measure reactive power of a load?

An ammeter and a wattmeter are the instruments needed.


Is reactive power greater than true power?

Use a wattmeter, as it only reads 'real power' of your load. Use an ammeter and a voltmeter, and the product of the two readings will give you 'apparent power' of your load. Since apparent power is the vector sum of real power and reactive power, use the following equation to find the reactive power of your load: (reactive power)2 = (apparent power)2 - (real power)2


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.


How would you measure power factor of the balanced three phase load by two wattmeter method?

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 currentVote noRating noWeight


What value of kvar in 25 hp motor?

Use a voltmeter and ammeter to measure the supply voltage and load current drawn by the motor. The product of these two readings will give you the apparent power in volt amperes. Then use a wattmeter to determine the true power of the machine, in watts. The reactive power, in reactive volt amperes, will then be the vector difference between the apparent power and the true power. 4hp = 1 KVAR, so for 25 hp, 25/4= 6025 KVAR

Related Questions

Why wattmeter measure the reactive power?

A watt meter will measure active power, not reactive power.


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 instrument can you use to measure reactive power of a load?

An ammeter and a wattmeter are the instruments needed.


To measure electrical power you would use a?

wattmeter


What is the function of watt meter?

The wattmeter is an instrument to measure the electrical power.


What are the uses of wattmeter?

Wattmeter is an intrument which is used to measure the power consumption of an Electric circuit or an appliance which is connected to the supply in terms of Watts.


What quantity is watt measured in?

A wattmeter is used to measure the power of a load.


What does upf stands in upf wattmeter?

UPF in a wattmeter stands for "Unity Power Factor." It refers to power factor optimization in electrical systems where the current and voltage are in-phase. This signifies efficient utilization of power without wastage in the form of reactive power.


Is it possible to measure power factor of the balanced three-phase load by two-wattmeter method?

yes.


Is reactive power greater than true power?

Use a wattmeter, as it only reads 'real power' of your load. Use an ammeter and a voltmeter, and the product of the two readings will give you 'apparent power' of your load. Since apparent power is the vector sum of real power and reactive power, use the following equation to find the reactive power of your load: (reactive power)2 = (apparent power)2 - (real power)2


Why watt-meter is required to measure real power delivered to a purely resistive load?

A wattmeter (not 'watt-meter') will always measure the true power of a load, regardles of whether that load is purely resistive or not. This is because a wattmeter effectively measures the in-phase component of the load current.


How do you find true power With power factor and apparent power?

to put out the power fector you have to divided apparent power with true power.AnswerYou can determine the true power of any load using a wattmeter. To find the apparent power, you use a voltmeter to measure the supply voltage and an ammeter to measure the load current, and multiply the two readings together.If you then want to go on to find the power factor, then you divide the true power by the apparent power. If you want to find the reactive power you use the following equation:(reactive power)2 = (true power)2 x (apparent power)2