Code reference · ABYC E-11 Tables 6A/VI, §11.14 (K=10.75), §11.10.1.1.1
Boat wiring ≠ house wiring: ABYC E-11 vs NEC
Marine DC systems follow ABYC E-11, not the NEC. Three differences that change answers: (1) the base ampacity table is single-conductor free air — bundled/duplex cable derates from there (0.70 for 2–3 conductors); (2) voltage drop uses the circular-mil method (CM = 10.75 × I × L(round-trip) ÷ E) with hard limits — 3% for panelboards, nav lights, electronics; 10% for non-critical loads; (3) engine spaces derate ampacity further (0.85 at 105°C insulation), and 60°C wire isn't permitted in them at all.
Also non-negotiable afloat: stranded tinned copper only (no solid Romex), and overcurrent protection within 7 inches of the power source (40/72 inches with sheathing depending on the source).
Run the numbers yourself
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More references: NEC Table 310.16 ampacity, explained · The NEC 705.12 120% rule, actually explained · What wire size for a 100 A sub panel? · NEC 625: EV charger circuit sizing · NEC 706: battery energy storage disconnects · NEC 240.4(D): the small-conductor overcurrent caps · all 97 references