I just replaced my failed group 24 battery and installed 2 new group 27 marine batteries from Walmart with a SurePower 1315a battery separator. I used a single battery tray that houses 2 group 27's batteries side by side. The main battery runs everything that the old single battery setup used to run ( bilge pump, blower, lights, etc) minus the radio. I rewired the radio so that it is powered by the auxiliary battery along with a Kicker KXM800.5. All future accessories will be powered by the auxiliary battery. The separator combines both batteries when either battery reaches 13volts or higher so that both batteries receives a charge (such as when the engine is running or when I'm plugged into the battery charger). When either battery falls below the 13volt threshold (such as when the engine is off), the battery pairs are separated so they can power each of their respective accessories and drain at separate rates. The alternator is wired directly the main battery while the battery charger is wired to the auxiliary battery. Since the 1315a is bidirectional, both batteries will be charged by the alternator when the engine is running, and both batteries will be charged by the battery charger when I'm plugged into the battery charger. The 1315a also has an "engine starting assist" feature in which when cranking the engine, the separator will compare the main battery voltage to the auxiliary battery voltage. If the main battery is lower than the auxiliary, the separator will combine both batteries so both batteries can start the engine. I have 2 voltage gauges wired to each battery and installed in the cockpit so I can monitor each battery independently and have spent much of the past 2 hours before sundown testing the separator and its functions. It this point, everything seems to be working great and it does exactly what it claims to do! The only thing I haven't been able to test is the "engine start assist" feature. I got a great deal on the Walmart Marine batteries that come with a 2 year exchange warranty. I have newer pictures in my reply post.
Joel
Joel
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