What Is the Voltage Drop for 4/0 AWG at 162A and 200 Feet?

4/0 AWG at 162A and 200 feet: 3.94V drop (3.28% on 120V), computed on the single-phase / DC basis. Every conductor has resistance, and longer runs at higher currents drop more voltage. Use this calculation to check whether your run clears the 3% branch-circuit drop target before pulling wire.

4/0 AWG, 162A, 200ft · single-phase / DC

3.94 V drop (3.28% on 120V)

On 120V circuit3.28%

On 240V circuit1.64%

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 →

Gauge

4/0 AWG

Amps

Feet

Drop @ 120V

3.94V (3.28%)

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)

V_drop = (2 × L × I × R) ÷ 1000

(2 × 200 × 162 × 0.0608) ÷ 1000 = 3.94 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 = (V_drop ÷ V_source) × 100

On 120V: (3.94 ÷ 120) × 100 = 3.28%

On 240V: (3.94 ÷ 240) × 100 = 1.64%

How This Estimate Changes with Run Length and Gauge

Gauge That Meets the 3% Target

The smallest gauge in our table that clears the 3% drop target at 162A over 200ft on 120V is 250 kcmil. Shorter runs, higher source voltage, or a higher drop tolerance (feeder-only applications often accept up to 5%) can change the pick. Run the full wire-size calculator with your actual variables.

Impact of Distance

Voltage drop is proportional to distance. Here is 4/0 AWG at 162A at different distances:

Distance	Drop (V)	% on 120V	% on 240V	NEC (120V)
25ft	0.4925V	0.4104%	0.2052%	OK
50ft	0.985V	0.8208%	0.4104%	OK
75ft	1.48V	1.23%	0.6156%	OK
100ft	1.97V	1.64%	0.8208%	OK
150ft	2.95V	2.46%	1.23%	OK
200ft	3.94V	3.28%	1.64%	Caution
300ft	5.91V	4.92%	2.46%	Caution

Same Run, Different Wire Gauges

How does wire gauge affect voltage drop for 162A at 200 feet on 120V single-phase / DC? Only gauges whose branch-circuit OCP cap is at or above the 162A load are listed, since thinner gauges would fail the ampacity check before drop even matters.

Gauge	Drop (V)	% on 120V	% on 240V	3% Target (120V)
4/0 AWG	3.94V	3.28%	1.64%	Caution
250 kcmil	3.34V	2.78%	1.39%	OK
300 kcmil	2.78V	2.32%	1.16%	OK
350 kcmil	2.38V	1.98%	0.9909%	OK
500 kcmil	1.67V	1.39%	0.6966%	OK
750 kcmil	1.11V	0.9234%	0.4617%	OK

Related Calculations

cable Wire size: 162A, 200ft bolt Watts to amps calculator functions Voltage drop formula

Frequently Asked Questions

What is the voltage drop for 4/0 AWG at 162A and 200ft?expand_more

4/0 AWG carrying 162A over 200ft has a 3.94V drop (3.28% on 120V). Reference: 1.64% on 240V.

What wire gauge should I use instead of 4/0 AWG for this run?expand_more

This run is at 3.28% on 120V, past the 3% branch-circuit drop target. If you want to land under 3% at 162A over 200ft on 120V, the smallest gauge in our table that clears it is 250 kcmil at 2.78%. Going up one size from 4/0 AWG is not always enough, each AWG step only drops the resistance by roughly 20-25%, so on long runs or high currents you often have to skip one or two sizes to meet the target. NEC 210.19(A) Informational Note 4 frames 3% as a recommendation, not a code requirement, so the right answer for you also depends on the load (motor startup, sensitive electronics) and how much drop is tolerable.

Does 4/0 AWG meet the 3% drop target at 162A and 200ft on 120V?expand_more

On 120V, this run sits at 3.28%, which is past the 3% branch target; within the 5% feeder+branch total. 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.

Is voltage drop worse on 120V or 240V?expand_more

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 1.64% on 240V versus 3.28% on 120V.

Why does distance affect voltage drop?expand_more

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.