Pacific Yacht Systemsvideo

Top Tips for Wiring A Battery Isolator on Your Boat

20 July 2021 · 5 min · 19K views

What this video covers

Installing a battery isolator requires rerouting the alternator output away from the starter solenoid.2:04 In standard marine electrical systems, the alternator connects to the starter solenoid, creating a daisy chain that complicates charging.1:22 To isolate the battery banks, the alternator output must run directly to the battery isolator, which then distributes current to the house and engine batteries.2:20 The isolator must connect to the unswitched positive distribution, meaning it remains wired directly to the batteries regardless of the position of the battery switch.2:35 The starter should remain connected to an engine battery switch.3:10 Every connection to a battery requires a fuse for safety.3:32 Jeff Cote of Pacific Yacht Systems recommends using Marine Rated Battery Fuses (MRBF), specifically Blue Seas models 2151 and 5191, for these applications.3:48 Proper installation ensures the isolator manages charging paths independently of the starter circuit.

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