46 CFR § 111.05-31 - Grounding conductors for systems.

---
identifier: "/us/cfr/t46/s111.05-31"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 111.05-31 - Grounding conductors for systems."
title_number: 46
title_name: "Shipping"
section_number: "111.05-31"
section_name: "Grounding conductors for systems."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "J"
subchapter_name: "ELECTRICAL ENGINEERING"
part_number: "111"
part_name: "ELECTRIC SYSTEMS—GENERAL REQUIREMENTS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "46 U.S.C. 3306, 3703; DHS Delegation No. 00170.1, Revision No. 01.2. Section 111.05-20 and Subpart 111.106 also issued under sec. 617, Pub. L. 111-281, 124 Stat. 2905."
regulatory_source: "CGD 74-125A, 47 FR 15236, Apr. 8, 1982, unless otherwise noted."
cfr_part: "111"
---


# 111.05-31 Grounding conductors for systems.

(a) A conductor for grounding a direct-current system must be the larger of:

(1) The largest conductor supplying the system; or

(2) No. 8 AWG (8.4mm
<sup>2</sup>).

(b) A conductor for grounding the neutral of an alternating-current system must meet Table 111.05-31(b).

Table 111.05-31(**b**)—Neutral Grounding Conductor for Alternating-Current System

|  |  |  |
| --- | --- | --- |
|  | 2 (33.6) | 8 (8.4) |
| 2 (33.6) | 0 (53.5) | 6 (13.3) |
| 0 (53.5) | 3/0 (85.0) | 4 (21.2) |
| 3/0 (85.0) | 350 MCM (177) | 2 (33.6) |
| 350 MCM (177) | 600 MCM (304) | 0 (53.5) |
| 600 MCM (304) | 1100 MCM (557) | 2/0 (67.5) |
| 1100 MCM (557) |  | 3/0 (85.0) |