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Explain the two-wattmeter method in detail for a balanced 3 phase star or delta connected load along with its necessary circuit, derivation and phasor diagrams. In a balance three phase 400 V circuit, the line current is 115.5 A. when the power is measured by two wattmeter method, one meter reads 40 KW and other reads zero. What is the power factor of the load? If the power factor were unity and the line current is same, what would be the reading of each wattmeter?
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Explain the two-wattmeter method in detail for a balanced 3 phase star...
Two-Wattmeter Method for Balanced Three-Phase Load


Circuit Diagram

The circuit diagram for a balanced three-phase star or delta connected load is shown below:

![circuit_diagram](
https://www.edurev.in/api/download/eyj0exaioijkv1qilcjhbgcioijiuzi1nij9.eyjzdwiioijhzg1pbje5otk3qgdtywlslmnvbsisimp0asi6ijizmtk2nzuynzu5nzkilcjpc3mioijhcgkifq.4jkywvk5w1vxhjqmc2fx3fpyv7klrzpnkriw8mgmmxw)
https://www.edurev.in/api/download/eyj0exaioijkv1qilcjhbgcioijiuzi1nij9.eyjzdwiioijhzg1pbje5otk3qgdtywlslmnvbsisimp0asi6ijizmtk2nzuynzu5nzkilcjpc3mioijhcgkifq.4jkywvk5w1vxhjqmc2fx3fpyv7klrzpnkriw8mgmmxw)


Derivation

The two-wattmeter method is used to measure the power in a three-phase circuit. The method is based on the fact that the total power in a three-phase circuit can be determined by measuring the power in two of the three phases. The third phase power can be calculated using the formula P3 = Ptotal - P1 - P2.

Phasor Diagrams

The phasor diagrams for the two-wattmeter method are shown below:

![phasor_diagram](
https://www.edurev.in/api/download/eyj0exaioijkv1qilcjhbgcioijiuzi1nij9.eyjzdwiioijhzg1pbje5otk3qgdtywlslmnvbsisimp0asi6ijizmtk2nzuzmdg5mzkilcjpc3mioijhcgkifq.7kuh0vj6nmjnvzk2d5gg5ztjdd2igclkvy2gwqcvzby)
https://www.edurev.in/api/download/eyj0exaioijkv1qilcjhbgcioijiuzi1nij9.eyjzdwiioijhzg1pbje5otk3qgdtywlslmnvbsisimp0asi6ijizmtk2nzuzmdg5mzkilcjpc3mioijhcgkifq.7kuh0vj6nmjnvzk2d5gg5ztjdd2igclkvy2gwqcvzby)


Calculation

Given, line voltage (VL) = 400 V, line current (IL) = 115.5 A, one wattmeter reading (W1) = 40 kW, and the other wattmeter reading (W2) = 0.

The total power (Ptotal) can be calculated using the formula Ptotal = W1 + W2 = 40 kW.

The power factor (PF) can be calculated using the formula PF = Ptotal / (VL x IL x √3) = 0.8.

If the power factor were unity (PF = 1) and the line current is the same, then the reading of each wattmeter would be W1 = W2 = Ptotal / 2 = 20 kW.
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Explain the two-wattmeter method in detail for a balanced 3 phase star or delta connected load along with its necessary circuit, derivation and phasor diagrams. In a balance three phase 400 V circuit, the line current is 115.5 A. when the power is measured by two wattmeter method, one meter reads 40 KW and other reads zero. What is the power factor of the load? If the power factor were unity and the line current is same, what would be the reading of each wattmeter?
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Explain the two-wattmeter method in detail for a balanced 3 phase star or delta connected load along with its necessary circuit, derivation and phasor diagrams. In a balance three phase 400 V circuit, the line current is 115.5 A. when the power is measured by two wattmeter method, one meter reads 40 KW and other reads zero. What is the power factor of the load? If the power factor were unity and the line current is same, what would be the reading of each wattmeter? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about Explain the two-wattmeter method in detail for a balanced 3 phase star or delta connected load along with its necessary circuit, derivation and phasor diagrams. In a balance three phase 400 V circuit, the line current is 115.5 A. when the power is measured by two wattmeter method, one meter reads 40 KW and other reads zero. What is the power factor of the load? If the power factor were unity and the line current is same, what would be the reading of each wattmeter? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Explain the two-wattmeter method in detail for a balanced 3 phase star or delta connected load along with its necessary circuit, derivation and phasor diagrams. In a balance three phase 400 V circuit, the line current is 115.5 A. when the power is measured by two wattmeter method, one meter reads 40 KW and other reads zero. What is the power factor of the load? If the power factor were unity and the line current is same, what would be the reading of each wattmeter?.
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