WireMath

Home › Wire size by amps › 250 amp

What size wire for 250 amps?

Advertisement
250 kcmil copper

minimum for 250 A (75 °C column, NEC 310.16) · 350 kcmil aluminum

250 amp wire size by distance (3% voltage drop, copper)

One-way distance120 V240 V
25 ft250 kcmil250 kcmil
50 ft250 kcmil250 kcmil
75 ft250 kcmil250 kcmil
100 ft250 kcmil250 kcmil
125 ft250 kcmil250 kcmil
150 ft300 kcmil250 kcmil
200 ft400 kcmil250 kcmil
250 ft500 kcmil250 kcmil
300 ft600 kcmil300 kcmil

Load assumed at the full 250 A. For continuous loads the circuit must be sized at 125% of the load (e.g. a 200 A continuous load on a 250 A breaker).

Check your exact run

FAQ

What size wire for a 250 amp circuit?

250 kcmil copper or 350 kcmil aluminum at 75 °C for short runs; longer runs need larger wire to limit voltage drop.

Can I use 250 kcmil on a 250 amp breaker for 150 feet?

Check voltage drop: see the distance table on this page.

Other circuit sizes

Advertisement
XFacebookRedditWhatsAppLinkedIn

Free calculator by WireMath

Advertisement