Keeping House & Stereo Battery Banks Seperated

[Murphy8166]

It's been years since I have done a larger (for me) stereo in a boat and this is the year I want to do something a bit different.  My dealer installs a couple Full River - Full Throttle batteries in the boat which in the past have been fine.

I want to add a couple additional batteries such as Full River Deep Cycles and I am wondering if I just keep the two banks separate at all times.  Stereo and amps to Stereo Bank and Boat Electronics to House Bank?

Also - When doing larger stereos - do you all suggest running everything through the supplied battery switch or adding another switch.  Concerned about amperage pull versus limits of Malibu OEM Battery switch/

Thanks for weighing in here.

[Brandonloos21]

We talked a little regarding your stereo build!

Salt 200.4 amp running cabins 325x4 

Salt 200.4 amp running rev 10’s 700x2

Salt 2k amp running 12w6 2000x1 (this amp is pretty overpowered for 12w6. You could add another 12a6, go with salt 1k, or upgrade sub to a larger w7, or even 2 of them.)

I would keep the starting battery bank (1 or 2 starting batts) and have this wired so position 1 on the switch. I would build a house/stereo bank of around 400AH (rule of thumb is generally 100ah/1000watts), and have this connected to position 2. (Make sure that all batteries for each bank are of same size and model).

With all of that in mind, you’ll be in the range of 4000rms. Battery switch stock is rated for 350a continuous and 600a (5min intermittent). 4000 rms stereo at full tilt would be MAX 333 amps at 12v. Keep in mind, this is never going to be possible for all of your amps to pull 333 amps at one single time. So with this in mind, stock batt switch is good! With this in mind, you can have your stereo distro connected straight to the batt switch if you want, but keep in mind stereo will be run off whatever position switch is at. Other option is to connect stereo straight to house/stereo batteries, the only difference here is that you can switch your boat to POS1, charge the cranking batteries while underway, and still be pulling off of your stereo bank without alternator charging it.

I don’t think that a 4000 watt system is large enough to put enough strain on an alternator to be detrimental, though I would make sure you have the upgraded model at least. 

 

Edited February 1, 2023 by Brandonloos21

[MLA]

On 1/31/2023 at 12:36 PM, Murphy8166 said:

Stereo and amps to Stereo Bank and Boat Electronics to House Bank?

This would require 3 banks, is that your plan? If so, then the amperage capacity of the OEM battery switch is a moot point, as it would only handle 2 banks. 

As to amp draw through the switch, the small M series switch has a 300A continious and the larger E series is rated for 350A continious.