1.6 KiB
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What is the best utility voltage to operate this motor at?
V_{util}=480V -
What is the synchronous speed of this motor?
n_s=120{f\over p}=120*{60Hz\over 6\ poles}\ \overline{\underline{|n_s=1200rpm|}} -
How many poles does this motor have? 6 poles, 2 for each phase.
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What is the slip of this motor?
s={n_s-n\over n_s}={1200rpm-1080rpm\over1200rpm}\ \overline{\underline{|s=0.1|}} -
What is the mechanical output in HP of this motor at full speed?
15hp(into watts)times efficiency\ \overline{\underline{|HP=12.75hp|}} -
What is the X/R ratio of the motor?
12.75hp*746w/hp=9511.5W\ S={P\over pf}={9511.5W\over0.85}=11190VA\ Q=\sqrt{S^2-P^2}=\sqrt{11190^2-9511.5W^2}=5894.7VAR\ {X\over R}={P\over Q}={9511.5W\over 5894.7VAR}=1.613 -
What is the total impedance of this motor at full load (magnitude and angle)?
|Z|=\sqrt{R^2+X^2}=\sqrt{24.22\Omega^2+39.09\Omega^2}\ <Z=tan^{-1}({X\over R})=tan^{-1}(1.613)\ Z=45.968\Omega<58.2^\circ -
What is the resistive impedance of this motor at full load (ohms)?
R={V^2\over P}={480V^2\over9511.5W}\ \underline{\overline{|R=24.22\Omega|}} -
What is the reactive impedance of this motor at full load (ohms)?
X={V^2\over Q}={480V^2\over5894.7VAR}\ \overline{\underline{|X=39.09\Omega|}} -
What is the full load active power drawn by this motor (kW)?
9.5kW -
What is the full load reactive power drawn by this motor (kVAR)?
5.8kVAR