NEC ReferenceNEC 2023 · 2026 · Updated May 2026

NEC Article 230: Electrical Service Requirements

NEC Article 230: Services covers Overhead Clearances through Emergency Disconnect (NEC 2020+). This guide explains each section with practical interpretation, common mistakes, and how these rules apply to real projects.

230.24 Overhead Clearances

Service drop clearances above finished grade: 10 feet at the service entrance point, 12 feet above residential driveways and commercial areas accessible only to pedestrian traffic, and 18 feet above public roads and commercial parking lots. These clearances apply to the conductors between the utility pole and your weatherhead.

The service point (where utility ownership ends and your wiring begins) is defined by the utility, not the NEC, and determines who pays for repairs. For new construction, coordinate the service point location with your utility before setting the meter base height.

230.30-32 Underground Service

Underground service laterals follow burial depth requirements in Table 300.5: direct burial cable requires 24 inches of cover, PVC conduit requires 18 inches, and rigid metal conduit (RMC) requires only 6 inches. Under a residential driveway, add 6 inches to the direct burial depth.

Use PVC Schedule 80 for the riser portion (where conduit emerges from ground to meter) because it withstands physical damage better than Schedule 40. USE-2 or XHHW-2 conductors are rated for direct burial and wet locations. Mark the trench route before backfilling and consider running a spare conduit for future use.

230.70-82 Service Disconnect

The service disconnect (main breaker) must be at a readily accessible location nearest the point of service entrance. NEC 230.71 limits you to a maximum of six disconnects to shut off all power (the "six throw rule"), though most modern homes use a single main breaker.

The disconnect must be rated for the available fault current at the service point. NEC 2020 Section 230.85 added a requirement for an emergency disconnect on the exterior of one- and two-family dwellings, accessible to first responders without entering the building.

If your main panel is indoors, you may need a separate exterior disconnect to comply.

Grounding Electrode System

Every service entrance requires a grounding electrode system connecting the electrical system to earth. The preferred electrode types per NEC 250.52 are: concrete-encased electrode (UFER ground, 20+ feet of rebar in the foundation), metal water pipe (first 5 feet entering the building), ground rods (8 feet driven into soil, two required unless one tests at 25 ohms or less per 250.56), and building structural steel.

The grounding electrode conductor (GEC) is sized from Table 250.66 based on the largest service conductor. For a typical 200A service with 4/0 aluminum service conductors, the GEC is 4 AWG copper. Do not confuse the GEC with the equipment grounding conductor (EGC) - they serve different purposes.

230.85 Emergency Disconnect (NEC 2020+)

NEC 2020 Section 230.85 requires one- and two-family dwellings to have an emergency disconnect at a readily accessible outdoor location. This allows firefighters and paramedics to shut off all power from outside without entering the building. The disconnect must be installed at a readily accessible location outdoor and be marked as "Emergency Disconnect" with red letters on a white background.

For homes with an existing indoor main panel, compliance typically requires either relocating the panel to an exterior wall or adding a separate outdoor disconnect ahead of the indoor panel. This requirement applies to new construction and services replaced after the adoption date of NEC 2020 in your jurisdiction.

Key NEC Tables Referenced

Frequently Asked Questions

What does NEC Article 230 cover?

Article 230 covers services requirements. Key sections include 230.24 Overhead Clearances and 230.30-32 Underground Service. It applies to all electrical installations in the United States.

Where can I find the full text of Article 230?

The full NEC is published by NFPA and available at nfpa.org. Many libraries provide free access. Your local building department also has copies available for reference during permit applications.

Does Article 230 apply to existing wiring?

The NEC applies to new installations, modifications, and additions. Existing wiring that was code-compliant when installed is generally grandfathered unless a renovation triggers an upgrade requirement. Check with your local AHJ (authority having jurisdiction).

When did the current Article 230 requirements take effect?

NEC 2026 is the latest published edition (effective September 2025). NEC 2023 remains the most widely adopted edition by states. Adoption varies - check your state adoption status on our state code pages.

Requirements vary by state. NEC edition, licensing, permits, and GFCI rules differ by jurisdiction. Check your state or pick it below for personalized info across WireRef.
This guide provides practical interpretation of NEC requirements. Always verify with your local AHJ and the current NEC edition adopted in your jurisdiction. WireRef is a reference tool and does not replace licensed professional judgment.

NEC references verified May 2026