Sailing Uma · video

What this video covers

Dan and Kika on Uma are mid-refit, installing a new 48-volt lithium battery bank as the first major electrical system step.▶ 0:01 The previous setup — twelve Battle Born 12-volt 100 Ah LFP drop-in batteries wired in series-parallel to reach 48 volts — failed without warning two or three times over five to six years when the sealed internal BMS tripped on a fault, blacking out the entire boat and forcing a sail to a marina to reset via shore power.▶ 7:37 The new system uses ten Victron NG 100 Ah 48-volt batteries (no series wiring required), split into two banks of five: one in the cockpit locker, one under the companionway steps, separated by a watertight bulkhead.▶ 12:05 Total capacity is roughly 50 kWh — double the previous bank at half the weight.▶ 11:59 Victron was chosen over MG and EP Technologies for its waterproof plastic housing, the modular Lynx bus bar system, external BMS with networked monitoring, and known compatibility with their existing Oceanvolt motor system.▶ 12:33 A design problem remains: ABYC standards require each of the ten batteries to have its own Class T fuse within seven inches of the positive terminal, and no off-the-shelf compact fuse holder exists for the application, so a custom bracket solution is still being developed.▶ 16:59

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