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Solve the numerical on paper and enter the final answers in Moodle The output of the 3 -phase, 400 V induction motor is 16 kW and operates at power factor of 0.8 lagging with an efficiency of 84%. Calculate the reading on each of the two wattmeter connected to measure the input. The value of P1​ is =

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Final answer:

To calculate the readings on the two wattmeters, we need to first calculate the total input power of the motor using its efficiency and output power and then use the 2-wattmeter method formulas incorporating the given power factor to find the two readings.

Step-by-step explanation:

The student is asking how to calculate the reading on each of the two wattmeters connected to measure the input power of a 3-phase, 400 V induction motor. given that the motor has an output of 16 kW, operates at a power factor of 0.8 lagging, and an efficiency of 84%, we shall first find the total input power and then divide it between the two wattmeters based on the formula for 2-wattmeter method used in 3-phase systems.

The formula for input power (Pi) is given by Pi = Po / efficiency, where Po is the output power. Calculating Pi, we get Pi = 16000 W / 0.84 = 19047.62 W. because the power factor is 0.8 lagging, we can use the formula for the readings of two wattmeters: P1 = 0.5 * Pi * (1 + cos(Φ)) and P2 = 0.5 * Pi * (1 - cos(Φ)), where Φ is the phase angle, which can be found by cos(Φ) = power factor = 0.8. assuming a balanced load and using the formulas, the wattmeter readings can be calculated, which will be the final answer populated into Moodle.

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