Power Factor

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Power Factor
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A Poor Power Factor

• Increases your electricity bill
• Increases transformer and cabling losses
• Means higher rated switchgear

But power factor correction capacitors can
improve it
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The Power Triangle
cos
?
P
Power Factor

VI
VI
VI
sin
?
?
VI
cos
?
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The Horse Barge Analogy
Useful Work
Horse's Effort
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Why Poor Power Factor Increases Energy Costs
Example Motor rated 15kW, Efficiency 92.0,
Input 16.3kW Power factor 1.00, Current
22.7A Power factor 0.85, Current 26.7A Supply
rated 415V, 19.5kVA