Code Change Summary: Revisions made to the GFPE and GFCI requirements.

In the 2023 NEC^® several changes were made in Section 555.35 to reorganize the section and separate the different feeder and branch circuit requirements for docking facilities (other than floating buildings). Before this reorganizing occurred, both feeder and branch-circuit conductors installed on docking facilities were required to have Ground-Fault Protection of Equipment (GFPE) set to open at currents not exceeding 100 milliamperes.

Now, Section 555.35(A) applies only to feeders and specifies that feeders installed on docking facilities shall have listed GFPE, rated not more than 100 milliamperes. Coordination with downstream GFPE is permitted at the feeder overcurrent protective device.

Section 555.35(B) addresses branch circuits for docking facilities and is broken down into two categories as follows:

(1) Receptacles Providing Shore Power. Listed GFPE, rated not more than 30 milliamperes, shall be provided for receptacles installed in accordance with 555.33(A), which covers the installation requirements for shore power receptacles including enclosure types, strain relief, and circuitry. Note that “Shore Power” is defined in Article 100 as the electrical equipment required to power a floating vessel including, but not limited to, the receptacle and cords. This definition is general in nature and includes most any power connection to a boat and does not limit the requirements in Section 555.35(B) only to boats anchored against the shoreline.

(2) Outlets for Other than Shore Power. Outlets supplied by single-phase branch circuits not more than 150 volts to ground and 60 amperes, and outlets supplied by three-phase branch circuits 150 volts or less to ground, 100 amperes or less, shall be provided with Ground-Fault Circuit-Interrupter (GFCI) protection for personnel.

Another change occurred in 555.35(D) which covers leakage current measurement devices. The rules in this section apply to installations where more than three receptacles supply shore power. For these situations, a leakage current measurement device (listed for use in marina applications) shall be available and used to determine leakage current from each boat that will utilize shore power. The listing requirement for the leakage current measurement device for use in marina applications becomes effective January 1, 2026.

Docking facilities with the ability to measure leakage current for boats utilizing shore power can pinpoint an individual boat that has defective wiring or other problems contributing to hazardous voltage and current.

The future effective date for product listing of leakage current measurement devices provides time to finalize the safety standard for testing equipment and for testing equipment manufacturers to come up with a product that complies with the standard. These devices are intended to be able to detect an individual boat with a potential electrical problem such as defective wiring or a modified cord plug end that may contribute to hazardous voltage and current in the area.