Table of Contents
- 1 How does 2 wattmeter method measure power factor?
- 2 What will be the reading of two wattmeter in three phase power measurement if the power factor is zero?
- 3 What will be reading on wattmeter when two wattmeter method is used for measurement of power with load PF 0.5 lag?
- 4 How does a wattmeter measure active power?
- 5 When do you use the two wattmeter method?
- 6 How are wattmeters used to measure three phase power?
- 7 What is the two watt meter balanced load condition?
How does 2 wattmeter method measure power factor?
Similarly, power measured by the wattmeter-2 is, W2 = VL IL cos(30 + 0) = √3/2 VL I. Hence, at unity power factor, both the wattmeters read half the value of total power consumed by the load i.e., both wattmeters read the same values.
What will be the reading of two wattmeter in three phase power measurement if the power factor is zero?
Thus we see that, when power factor of load is 0.5 lagging then power is only measured by first wattmeter and reading of second wattmeter is ZERO. Case3: When power factor of load is zero. Thus we see that, when power factor of load is zero then one wattmeter reads +ive while second wattmeter reads –ive.
How does a wattmeter measure power factor?
The power factor is the calculated by dividing the total watts from each meter by the total volt-amps. With a three-phase, three-wire system, power factor should be measured using the three wattmeter method instead of the two wattmeter method if the load is unbalanced, that is if the phase currents are different.
What will be reading on wattmeter when two wattmeter method is used for measurement of power with load PF 0.5 lag?
Thus we see that, when power factor of load is 0.5 lagging then power is only measured by first wattmeter and reading of second wattmeter is ZERO.
How does a wattmeter measure active power?
One wattmeter measures voltage between the R and T phases, a second wattmeter measures voltage between the S and T phases and a third wattmeter measures voltage between the R and S phases. The phase currents are measured by each wattmeter. The two-wattmeter method is still used to calculate total power. Pt = P1 + P2.
What two values does a wattmeter measure?
A wattmeter does a complex job, measuring the power flowing through an electrical circuit. It simultaneously measures the voltage and current values and multiplies them to give power in watts.
When do you use the two wattmeter method?
Similarly, delta connected loads are also used. Two wattmeter method can be used irrespective of balanced or unbalanced load. The algebraic sum of two wattmeter reading gives the total power in the 3-phase, 3 wire star-connected or delta connected load circuits whether the load is balanced or unbalanced.
How are wattmeters used to measure three phase power?
As the name indicates, in this method two wattmeters are used to measure three-phase power. This is the most popular method among the three. This method is generally used for the measurement of power in 3 phase, 3-wire load circuits. It can be used to measure power in star/delta connected load in balanced or unbalanced condition.
How is the total power of a wattmeter calculated?
The current coil of each wattmeter carries the current of one phase only and the pressure coil measures the phase voltage of the phase. Hence, each wattmeter measures the power in a single phase. The total power in the load is given by the algebraic sum of the readings of the three wattmeters. P = W1 + W2 + W3
What is the two watt meter balanced load condition?
The following article describes the two wattmeter method at balanced load condition. What is Two Wattmeter Method? A three-phase two-watt meter measures the current and voltage from any of the 2 supply lines of 3 phase corresponding to the 3rd supply line of 3 phase.