Ask, the resistance/phase of the load

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SUMMARY

The discussion focuses on calculating the resistance and phase angle of a balanced 3-phase purely resistive load using given formulas and values. The participant utilized the equations W1 = VL IL cos(30-theta) and W2 = VL IL cos(30+theta) with VL = 110V and IL = 0.86A to derive W1 and W2 as 77W and 76.5W respectively. The phase angle theta was calculated as 0.810 radians, resulting in a power factor (pf) of 0.999. The participant questioned whether to use the formula R = V/I or the wattmeter results for calculating resistance, confirming that R = 110V / 0.86A yields a resistance of 127.91 ohms.

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Homework Statement



I was asked to calculate the value of the resistance/phase of the load in balanced 3-phase purely resistive load. it stated that there are two different ways to obtain the solution.

Homework Equations



W1 = VL IL cos (30-theta)
W2 = VL IL cos (30+theta)

where Voltage Line = 110, Line current = 0.86, W1=77 and W2=76.5

The Attempt at a Solution



W1+W2=153.5

theta=tan-1 ([tex]\sqrt{3}[/tex] * (W1-W2)/(W1+W2))

thus, I obtained theta = 0.810 where cos theta (pf) = 0.999

from this, how I calculated the resistance? is it only R=V/I = 110/0.86 = 127.91? or using the wattmeter result?
 
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help..anyone?
 
There are a few things I don't understand about your question... But, I will be direct, first.

You know that R = V/I. Also, you have figured out what the resistance is and what the phase is. So what's your problem?
 

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