Breaker Sizing Calculator for North Dakota
NEC 2020 breaker sizing math for EV charger installers working in North Dakota.
Every EVSE branch in North Dakota is treated as a continuous load per NEC 2020 Article 625 — the OCPD must be sized at 125% of the EVSE's listed maximum draw.
Worked example for North Dakota
A 80 A continuous EV load requires a breaker rated 100 A (80 × 1.25 = 100.0 A, rounded up to the next standard size). The conductor downstream must carry that 100 A after North Dakota's 0.88× ampacity correction.
Code & Utilities
EV installations in North Dakota are governed by the 2020 National Electrical Code, in force since 2023. That includes Article 625 (Electric Vehicle Power Transfer System) requirements: 125% continuous-load sizing on EVSE branch circuits, GFCI protection at outdoor receptacles, and provisions for energy management systems on shared circuits.
In North Dakota, you'll most often interconnect with Xcel Energy North Dakota, Otter Tail Power, Montana-Dakota Utilities. Each has its own service-upgrade timeline, EV rebate availability, and metering rules — confirm them before quoting commercial work.
Climate & Ampacity
North Dakota's representative summer design ambient is around 91°F, which yields a 0.88× ampacity correction factor at 75°C terminations per NEC 310.15(B)(1). Because the correction is below 0.9, conductors that "look fine" on a 30°C ampacity table will not carry their nameplate current here — always derate explicitly.
North Dakota takeaway
Use a 100%-rated breaker only when the panel and breaker are both listed for 100% continuous duty — otherwise the 125% rule applies. North Dakota inspectors enforce this rigorously on Article 625 work.