advice on adding house battery and switch

surfbird

I would like to add a house battery and I am confused about the differences between switches that isolate batteries 1 and 2 separately and have a 1+2 setting and those that isolate battery 1 and have a "combined" setting (as shown in the link below).
http://bluesea.com/files/images/products/7650.jpg

Will a 300 ampere unit work or should I get the heavy duty higher amp version?

Do I need a charging relay?

Jim

Adeline · Posted: Sat Nov 10, 2007 3:01 pm Post subject:

After I added a house battery and an Off,1,2,both switch I decided that I wanted to automate my management. I ended up getting a Blue Seas 7600

and their 5511e

which I mounted on an acrylic board along with both positive and negative busbars.

Upon starting the engine, once the starting battery has reached a preset voltage the 7600 closes the circuit(combines) and starts charging the house battery. When I kill the motor and the starting battery voltage drops to a preset voltage it is disconnected, preserving it's state of charge. The presets, both combine and disconnect, are selectable. This setup has eliminated the possibility of inadvertently discharging my starting battery.

thataway · Posted: Sat Nov 10, 2007 9:49 pm Post subject:

The 300 amp switches are rated 500 amps intermittant and 700 cranking. This should be fine for any engine you put on a 22.

We also use the Blue Seas combiners on our boats, as well as the battery switch--if you have failure of the combiner, you can always fall back on the switch.

Rob & Karen · Posted: Sat Nov 10, 2007 11:57 pm Post subject:

I am interested in an ACR for our boat, but I am not clear on how it would interact with our existing 3-bank Guest battery charger, which is hard wired to our two batteries.

The Blue Seas web site says ACR's use mechanical relays controlled by a circuit that senses when a charging source is being applied to either battery. When a charge is being applied, the ACR closes after a short time delay and connects the two batteries.

I understand that this would be good when the alternator is the charging source, but how would this work when the battery charger is the charging source?

Thanks for any assistance.

Rob

thataway · Posted: Sun Nov 11, 2007 6:21 pm Post subject:

It turns the relay on, unless you isolate the ARC from the batteries with the battery switches. That is what we did on the Tom Cat.

On the CD 25, I didn't do that, and when running the charger, it does come on. I probably will change the wiring of the 25. But the charger is not used much currently.

Most of these relays have duty cycles in the thousands, if not 100,000 cycles.

mikeporterinmd · Posted: Sun Nov 11, 2007 7:43 pm Post subject:

oldgrowth · Posted: Mon Nov 12, 2007 1:02 am Post subject:

I have the same setup as Adeline. I did put a LCD indicator light on the dash that lights up when I have my switch on to combine the batteries. The light acts as a reminder so I will not forget to turn the switch off. It is too easy to forget to turn it off, and can lead to the discharge of your starting battery.

When I am charging from a battery charger, I usually hook the charger to the house bank and the ACR will combine the batteries automatically.

When I extended my boat I moved it to under the engine well just above the batteries. Before it was inside the cabin because my batteries were under the port seat. I have had this setup for two years and haven’t had any trouble with it.

________
Dave