Dual battery question

RUFcaptain

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My 225 has dual batteries, when I took delivery the dealer told me to always use 1+2 mode. But I see on the Grady site NOT to use the batteries in this fashion.
So now I'm confused, is there a problem running them 1+2?
 

chesapeake

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RUFcaptain said:
My 225 has dual batteries, when I took delivery the dealer told me to always use 1+2 mode. But I see on the Grady site NOT to use the batteries in this fashion.
So now I'm confused, is there a problem running them 1+2?
.
I always run with the switch on all.
 

Salinity Now

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I ran mine with stbd motor on 1, port motor on 2.

Hadnt charged the batteries in over a year and always work like a charm.
 

Curmudgeon

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The deal with running on 1+2, ALL, BOTH (whatever your switch says) is not when everything is good, it's when something isn't good. If you have an undetected electrical malfunction, you may kill or damage both batteries. Also depends on how your system is wired and how you maintain your batteries.

I have two identical batteries, but only one is in use at any given time. The one in use is primary, and the other is a fully charged 'reserve'. On my boat, the use of BOTH is an emergency procedure dictated by the primary being unable to crank the engine, and the outing is terminated once the engine is started. Something drew the primary down, and I'm gonna get home before the same thing happens to the reserve. It's what works for me ... :wink:
 

seasick

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I usually run the out trip on one only. Assuming both are the same type, there is a case to be made for running on one and that is if it dies for whatever reason, you probably have a backup.
I try to alternate which one I use. On longer trips, I go out on one but often return on BOTH. That tops off both batteries. If the batteries are different types, brands or age, I would suggest running on one only at a time.
 

Pete1313

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If you have a single engine and dual batteries, best thing to do is to isolate a start battery and a house battery. Buy a compatible switch and VSR (voltage sensing relay) ... you will completely isolate your start battery from your electronics, and, guarantee (if installed properly) that you could run your electroncis down to zero and still have a full start battery.

When your start battery reaches 12.5 volts, it automatically parallels the house in to charge. If your start battery dips below 12.5 volts, it opens the circuit, isolating them.

BlueSea makes a great one, as does BEP/Marinco. Following links are just examples of the product - not endorsing any vendors. I have a Blue Sea ACR and it is great.

http://bluesea.com/products/7650

http://www.boat-superstore.com/store/p/ ... inco-.html