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How many amps can 3/0 AWG wire carry?

200 A — copper at 75 °C, NEC Table 310.16.

3/0 AWG copper carries 200 A at 75 °C, 165 A at 60 °C and 225 A at 90 °C under NEC Table 310.16, before derating. Aluminum at the same size is 155 A at 75 °C.

Safety first. These figures are an educational reference before derating, not a code substitute. Verify against the current NEC and have circuits reviewed by a licensed electrician.

3/0 AWG ampacity — copper vs aluminum

3/0 AWG ampacity by conductor material and insulation temperature rating.
Material 60 °C 75 °C 90 °C Breaker cap
Copper 165 A 200 A 225 A —
Aluminum 130 A 155 A 175 A —

Values are amps at a 30 °C ambient, before derating for temperature or conductor bundling. Most installations must use the 75 °C column regardless of the wire's own rating, because terminals and breakers are rated 75 °C (NEC 110.14(C)).

How far can you run 3/0 AWG at 200 A?

Ampacity answers whether a conductor will overheat. It says nothing about whether the voltage still arrives at the far end. Past roughly fifty feet, voltage drop is usually what really sets the wire size. These are the longest one-way runs that keep drop within the 3% recommended by the NEC 210.19(A) informational note, for 3/0 AWG copper carrying 200 A.

Maximum one-way run length for 3/0 AWG copper at 200 A by system voltage.
System Typical use Max run at 3% Drop at 100 ft
120 V standard receptacle and lighting circuits 146 ft 2.47 V
240 V ranges, dryers, EV chargers, feeders 291 ft 2.47 V
12 V DC automotive, marine, solar and battery runs 15 ft 2.47 V

Single-phase, one-way distance, copper at 20 °C. Aluminum reaches its limit at roughly 60% of these distances for the same size. The 3% figure is a recommendation in an informational note, not a code requirement.

3/0 AWG wire size — diameter, area and resistance

Diameter

0.4096 in · 10.405 mm

Cross-section

85.029 mm² · 167,806 cmil

Nearest metric size

95 mm² (rounds up)

Copper resistance

0.0618 Ω per 1000 ft @ 20 °C

Aluminum resistance

0.1032 Ω per 1000 ft

Area

167.806 kcmil

Diameter is computed from the ASTM B258 definition d = 0.005 × 92^((36 − n)/39), not read from a rounded table. Resistance uses the annealed-copper constant 10.371 Ω·cmil/ft at 20 °C.

What 3/0 AWG wire is used for

The 000 gauge mistake worth knowing

3/0 copper is the usual answer for a 200 A feeder at 75 °C, but 200 A services are far more often run in 4/0 aluminum because it costs a fraction as much for the same job — which is why two “200 amp wire size” answers can both be right.