NEC Article 230 — Service Conductors, Service Equipment, and the Six-Disconnect Rule
NEC 230 governs everything from the utility connection to the main breaker: service-entrance conductor sizing, service rating, the six-disconnect rule, and where the service disconnect must be located.
NEC 230 covers the service — everything from where the utility connects to the building through to the first means of disconnect. This article catches a lot of NJ rough-in failures.
Service-entrance conductor sizing (230.42): service conductors must have an ampacity not less than the maximum load they serve, with continuous loads at 125%. For typical residential 200 A service, that's #4/0 AL or #2/0 CU (per Table 310.16 at 75 °C terminations). PSE&G publishes a service-entrance spec that sometimes requires upsizing — verify with their meter spec sheet for your area.
Minimum service rating (230.79): dwelling-unit services are minimum 100 A for one-family dwellings (230.79(C)). Most modern NJ homes are 200 A; 320 A and 400 A services are increasingly common with EV chargers + heat pumps.
The six-disconnect rule (230.71): the service must have no more than 6 disconnects to disconnect ALL service-entrance conductors. The 2020 NEC tightened this — previously you could have up to 6 separate breakers. Now it's typically a SINGLE main breaker, OR a meter combo with up to 6 disconnects all in one location. Meter-main combo enclosures with multiple sub-feeds are a common Hudson County setup for two-family dwellings.
Disconnect location (230.70): the service disconnect must be installed at a readily accessible location either OUTSIDE the building or INSIDE nearest the point of entrance of the service conductors. NJ inspectors enforce "nearest the point of entrance" strictly — a panel halfway across the basement from where the service comes in fails.
Working space at the service: same as 110.26 — 36 inches deep, 30 inches wide, 6.5 ft tall. This is THE most-cited rough-in failure on service upgrades.
Service mast and weatherhead (230.54): the service mast must be sized to handle the mechanical load of the service drop. Schedule 80 PVC or galvanized rigid conduit, with proper weatherhead clearance from windows, doors, and the roof.
For service-upgrade SLDs, the free Malfettone Single-Line Diagram Builder at /tools/single-line-diagram has a "200A panel upgrade" template that includes the utility transformer, service-entrance conductors with conductor-count tick marks, meter, main breaker, panel, and grounding electrode system — the AHJ-format submission shape.
This guide is an educational summary written by a licensed NJ master electrician. It is not a substitute for the National Electrical Code or for the judgment of your local AHJ. For real permit work, verify every code interpretation with your authority having jurisdiction and a licensed electrician of record.