BoatHowTo · video

What this video covers

Nigel Calder explains the requirements for fusing an alternator output conductor when rerouting it directly to a house battery.0:18 While a 60-amp alternator cannot exceed the 102-amp capacity of a six-gauge cable, the connection point at the battery requires overcurrent protection to prevent a short circuit.0:23 The fuse must have an amp rating no higher than the conductor's ampacity, which in this case is 100 amps.2:13 ABYC standards generally require this protection device to sit within seven inches of the connection point to the battery or larger conductor.3:09 While circuit breakers often mount directly to bus bars, fuses may be placed up to 40 inches away with additional sheathing, or up to 72 inches from the battery under specific conditions.3:27 MRBF fuses mounted directly to a battery post provide a near-zero-inch unprotected wire length.3:45 Placing a fuse at the alternator itself is discouraged, as engine heat can melt the fuse and damage the alternator.1:52

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