Three Phase Power Equations
Electrical 3-phase equations
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Some common three phase power equations can be expressed as
Real Power
Wapplied = 31/2 U I cos Φ
= 31/2 U I PF (1)
where
Wapplied = real power (watts)
U = voltage (volts)
I = current (Amps)
PF = cos Φ = power factor (0.7 - 0.95)
For purely resistive load: PF = cos Φ = 1
Example - Resistive Load
For purely resitive load and power factor = 1, the real power in a 415 Voltage 20 Amps circuit can be calculated as
Wapplied = 31/2 (415 V) (20 A)
= 14400 Watts
= 14.4 kW
Total Power
W = 31/2 U I (2)
Brake Horsepower
WBHP = 31/2 U I PF μ / 746 (3)
where
WBHP = brake horse power (hp)
μ = device efficiency
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Related Topics
- Electrical - Amps and electrical wiring, AWG - wire gauge, electrical formulas, motors and units
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