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AC Voltage Drop Calculation Table

Estimate Voltage Drop

This table was calculated using the equation $latex V=I(R cos(\phi) + X sin(\phi))$ where $latex V$ is voltage, $latex I$ is current, $latex R$ is conductor resistance, $latex X$ is conductor reactance and $latex \phi$ is the power factor. This formulation is useful where specific load detail are known. Calculate the exact voltage drop here: AC Voltage Drop Calculator.

Line-to-Line Voltage Drop for 3-phase, 600 VAC, 60 Hz, 75°C (167°F) conductors in conduit

The units of tabulated values for a given wire size and power factor are V/(1000 ft-A). For example, a 3-phase circuit with #2 conductors feeding a 0.90 pf load drawing 10 A will drop 3.55 V every 1000 feet of circuit length.
Wire Sizepf=1.0pf=0.95pf=0.90pf=0.80pf=0.70
145.3695.1404.8884.3713.849
123.4643.3283.1692.8422.509
102.0782.0091.9181.7281.533
81.3511.3191.2651.1481.026
60.8490.8410.8120.7450.673
40.5370.5430.5290.4920.450
30.4330.4430.4340.4080.376
20.3460.3600.3550.3360.313
10.2770.2940.2920.2810.264
1/00.2080.2270.2290.2230.214
2/00.1730.1940.1970.1950.188
3/00.1370.1580.1620.1640.160
4/00.1090.1310.1370.1400.139
2500.0940.1170.1230.1290.130
3000.0780.1020.1090.1150.118
3500.0680.0910.0990.1060.109
4000.0610.0840.0920.0990.103
5000.0500.0740.0810.0900.095
6000.0430.0670.0750.0850.090
7500.0360.0610.0690.0790.085
10000.0310.0540.0630.0730.079