What Is the Voltage Drop for 2 AWG at 14A and 250 Feet?

2 AWG copper carrying 14 amps over 250 feet on a single-phase / DC circuit drops 1.36 volts (1.13% on a 120V source). This sits within the 3% branch target and the 5% feeder+branch total target that NEC 210.19(A) Informational Note 4 cites. Both are planning targets, not code requirements.

2 AWG, 14A, 250ft · single-phase / DC
1.36 V drop (1.13% on 120V)
On 120V circuit1.13%
On 240V circuit0.5658%

Circuit basis: This uses the single-phase / DC round-trip formula (factor of 2) for the voltage drop across the two circuit conductors. For a three-phase line-to-line run use the three-phase version of the page (append ?type=3ph). Switch to the three-phase version →

2 AWG
1.36V (1.13%)

Assumes a 120V source on a single-phase / DC circuit. Use the circuit-basis link above to switch between single-phase/DC and three-phase.

Voltage Drop Formula (single-phase / DC)

Vdrop = (2 × L × I × R) ÷ 1000

(2 × 250 × 14 × 0.194) ÷ 1000 = 1.36 V

DC and single-phase AC use the round-trip factor of 2. Current travels out to the load on one conductor and returns on another.

For a three-phase circuit at the same amps and distance, see the three-phase version (uses √3 instead of 2, so the drop is about 13.4% lower).

Percentage

%VD = (Vdrop ÷ Vsource) × 100

On 120V: (1.36 ÷ 120) × 100 = 1.13%
On 240V: (1.36 ÷ 240) × 100 = 0.5658%

How This Estimate Changes with Run Length and Gauge

Gauge Check

2 AWG clears the 3% drop target at these inputs. A smaller conductor may also meet it with less margin. See the minimum gauge for this load and distance.

Impact of Distance

Voltage drop is proportional to distance. Here is 2 AWG at 14A at different distances:

DistanceDrop (V)% on 120V% on 240VNEC (120V)
25ft0.1358V0.1132%0.0566%OK
50ft0.2716V0.2263%0.1132%OK
75ft0.4074V0.3395%0.1698%OK
100ft0.5432V0.4527%0.2263%OK
150ft0.8148V0.679%0.3395%OK
200ft1.09V0.9053%0.4527%OK
300ft1.63V1.36%0.679%OK

Same Run, Different Wire Gauges

How does wire gauge affect voltage drop for 14A at 250 feet on 120V single-phase / DC? Only gauges whose branch-circuit OCP cap is at or above the 14A load are listed, since thinner gauges would fail the ampacity check before drop even matters.

GaugeDrop (V)% on 120V% on 240V3% Target (120V)
2 AWG1.36V1.13%0.5658%OK
1 AWG1.08V0.8983%0.4492%OK
1/0 AWG0.854V0.7117%0.3558%OK
2/0 AWG0.6769V0.5641%0.282%OK
3/0 AWG0.5362V0.4468%0.2234%OK
4/0 AWG0.4256V0.3547%0.1773%OK

Frequently Asked Questions

2 AWG carrying 14A over 250ft has a 1.36V drop (1.13% on 120V). Reference: 0.5658% on 240V.
Motors run hotter and can have trouble starting under load. Incandescent and halogen lighting dims. Some electronics misbehave at the low end of their input tolerance. Energy is wasted as I²R heating in the conductor. These are performance issues; high drop is not itself a code violation unless the specific installation cites a hard limit.
On 120V, this run sits at 1.13%, which is within the 3% branch and 5% feeder+branch total drop targets. NEC 210.19(A) Informational Note 4 cites 3% for branch circuits and 5% for total feeder+branch drop as performance recommendations, not hard code requirements.
Same wire, same amps, same distance: the volts dropped are identical. But the percentage is worse on 120V because the drop is a larger fraction of the source voltage. This run would be 0.5658% on 240V versus 1.13% on 120V.
Voltage drop is proportional to distance. The formula multiplies by 2 × the distance (out and back). Doubling the run doubles the drop.
This calculator provides estimates for reference purposes only. Always consult a licensed electrician and verify compliance with the National Electrical Code (NEC) and local electrical codes before performing any electrical work.