Correct Answer:
�� To ensure the neutral current is zero
Question 1 |
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What is the reason for balancing the load across the three phases |
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Correct Answer:
�� IL
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In an RL Parallel circuit what is the lagging component |
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Correct Answer:
�� Fit p.f. correction capacitors across the load
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What can be done to improve the power factor of an industrial installation |
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Correct Answer:
�� 3488.37 VA
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If the true power is 3kW and the power factor is 0.86 what is the apparent power. |
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Correct Answer:
�� 48.81 degrees
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If R=7 ohms�and Xc=8 ohms what is the phase angle |
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Correct Answer:
�� 0.919
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If the phase angle is 23.185 degrees what is the power factor |
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Correct Answer:
�� 106.10 ohms
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What is the Ohmic value (or capacitive reactance) of a 30 micro Farad Capacitor |
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Correct Answer:
�� 25 kVAr
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If the apparent power is 50 kVA and the phase angle is 30 degrees what is the value of the reactive component |
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Correct Answer:
�� IL=Ip
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In a star connected system what is the relationship between Line Current and Phase Current |
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Correct Answer:
�� 45 degrees
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If the true power was 500 watts and the apparent power was 707.106 VA what would the phase angle be |
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Correct Answer:
�� V (Volts)
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In an RLC Parallel circuit which quantitiy remains constant |
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Correct Answer:
�� VL
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In an RL Series circuit what is the lagging component |
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Feedback: In an RL Series circuit what is the lagging component
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Correct Answer:
�� 0.636
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If R=7 and Z=11 what is the power factor |
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Correct Answer:
�� Ohms
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0 of 1 points � |
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What does the ratio W/VA produce: |
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Correct Answer:
�� To improve the power factor
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What is the purpose of the capacitor across the terminals of a fluorescent fitting used for: |
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Correct Answer:
�� 0.707
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If the true power was 500 watts and the apparent power was 707.106 VA what would the power factor be |
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Correct Answer:
�� Unity
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When W=VA what is the p.f |
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Correct Answer:
�� 1390 micro farads
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An RL circuit connected to a 50Hz supply consists of a 5 ohm resistor in series with an inductor of� 7.29mH. What size capacitor would you need to connect across the supply to correct the phase shift |
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Correct Answer:
�� VA (Volt Amps)
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On a power triangle what does the hypotenuse represent: |
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Correct Answer:
�� 120
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By how many degrees are the three phases separated |
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Correct Answer:
�� One third the power (p/3)
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What is the relationship between the power dissipated in a star connected system to that of a delta connected system |
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Correct Answer:
�� IL>Ip
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In a delta connected system what is the relationship between Line Current and Phase Current |
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Correct Answer:
�� 9.42 ohms
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What is the Ohmic value (or inductive reactance) of a 30 milli Henry (30mH) inductor |
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Correct Answer:
�� 1
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When R=Z what is the p.f |
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Correct Answer:
�� Z
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On an impedance triangle what does the hypotenuse represent: |
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Correct Answer:
�� 54.31 degrees
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If R=7 and Z=12 what is the phase angle |
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Correct Answer:
�� PowerFactor
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What does the ratio of R/Z produce: |
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Correct Answer:
�� XL = 2.29�ohms, p.f. = 0.909,�phase angle = 24.59 degrees
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An RL circuit connected to a 50Hz supply consists of a 5 ohm resistor in series with an inductor of� 7.29mH. What is the Ohmic value of the inductor, The power factor and the phase angle |
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Correct Answer:
�� 7.3mH
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In a series RL circuit�the value of R is 4 ohms and the phase angle is 30 degrees what is the� value of the inductor |
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Correct Answer:
�� I (Amps)
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In an RLC Series circuit which quantity remains constant |
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