Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Basic Wiring Diagram on how to install a dual battery switch

Posted by Cpelcher on 06/07/17 - 6:52 AM
#1

Good morning. Adding a 2nd battery and battery switch and I'm looking for a basic diagram or advice on the wiring for this. Been online, looked at a bunch of different diagrams and they all seem a little different to me. Just need the basic setup. Any help would be greatly appreciated. Thanks everyone!
Chris

Posted by PurrSeaStance on 06/07/17 - 9:46 AM
#2

In it's very basic use: Think of the 2 battery switch as a device to choose which battery (or both in "All" setting) to charge from your engine's alternator. This will also make the connection to the selected battery for re-starting the engine.
The red leads (positive) of the batteries are placed on the outside legs of the switch and the alternator + in the center of the switch (The part that rotates). All battery selector switches you buy should come with their specific diagram but this is the basic idea. The negative leads are all connected together on a bus. Make sure you use appropriately sized battery cables depending upon the distance from battery and the calculated voltage drop. Best practice is to keep the batteries and switch close together. Hope that helps a bit? Will

Posted by JRP on 06/07/17 - 1:41 PM
#3

Blue Sea Systems is a good resource:

https://www.bluesea.com/products/7650...Kit_-_120A

Posted by Mjfnet on 06/07/17 - 7:45 PM
#4

I installed the BlueSea system mentioned above this winter on my 170. I used the resources on their site they gave a lot o information there. The also have an iPhone app. The hardest part for me was going through the wire gauge charts deciding on what gauge to use and what size fuses to use. I leaned towards the larger side on the wire and not too large on the fuses when they were close. I couldn't be happier many trips so far this spring and plenty of power for starting and for my downrigger, depth finders etc.

Posted by gchuba on 06/08/17 - 7:44 PM
#5

The Blue Sea system allows for both batteries to always charge with one battery isolated. No issues as with the Perko switch where if you leave it on both......a bad battery can drain the charge of the good one. There is a "combine" feature with the Blue Sea system which allows the isolated battery to "jump" the other if it loses charge. Do study the installation.