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 Size	pf=1.0	pf=0.95	pf=0.90	pf=0.80	pf=0.70
14	5.369	5.140	4.888	4.371	3.849
12	3.464	3.328	3.169	2.842	2.509
10	2.078	2.009	1.918	1.728	1.533
8	1.351	1.319	1.265	1.148	1.026
6	0.849	0.841	0.812	0.745	0.673
4	0.537	0.543	0.529	0.492	0.450
3	0.433	0.443	0.434	0.408	0.376
2	0.346	0.360	0.355	0.336	0.313
1	0.277	0.294	0.292	0.281	0.264
1/0	0.208	0.227	0.229	0.223	0.214
2/0	0.173	0.194	0.197	0.195	0.188
3/0	0.137	0.158	0.162	0.164	0.160
4/0	0.109	0.131	0.137	0.140	0.139
250	0.094	0.117	0.123	0.129	0.130
300	0.078	0.102	0.109	0.115	0.118
350	0.068	0.091	0.099	0.106	0.109
400	0.061	0.084	0.092	0.099	0.103
500	0.050	0.074	0.081	0.090	0.095
600	0.043	0.067	0.075	0.085	0.090
750	0.036	0.061	0.069	0.079	0.085
1000	0.031	0.054	0.063	0.073	0.079