Box Fill Calculator for Louisiana

NEC 2020 box fill math for EV charger installers working in Louisiana.

Every EVSE installation in Louisiana eventually hits a junction or device box — disconnects, splice points, pull boxes — all of which must satisfy NEC 2020 Article 314.16 fill rules.

Worked example for Louisiana

A 4-11/16" square × 2-1/8" deep box has a 42.0 in³ volume. Each #6 Cu conductor counts as 5.0 in³. With a 2-conductor + EGC EVSE branch landing in the box plus a device, you consume roughly 15-20 in³, leaving plenty of headroom — but a 60 A multi-port pull box can fill quickly with #4 or #2 AWG conductors.

Code & Utilities

EV installations in Louisiana are governed by the 2020 National Electrical Code, in force since 2022. 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 Louisiana, you'll most often interconnect with Entergy Louisiana, Cleco Power, SWEPCO Louisiana. Each has its own service-upgrade timeline, EV rebate availability, and metering rules — confirm them before quoting commercial work.

Climate & Ampacity

In Louisiana, the 95°F summer ambient drives a 0.88× 75°C ampacity correction. Bake this into every Level 2 and DCFC conductor pick before you commit to a wire size. 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.

Louisiana takeaway

Always run box-fill math when the EVSE disconnect lives more than a few inches from the unit itself — that intermediate junction is where Louisiana inspectors most often catch fill violations.