# Need Help Adding a "House" Battery to My Starweld Fusion 20 Pro Boat



## ohiojmj (Apr 16, 2004)

How do you wire a new "house" battery to complement an existing starting battery? I want to start my Yamaha F150 or T9.9 in case I run down the battery running VHF, two Helix GPS/Fishfinders, etc. or have a battery failure. I plan to use a 4 way Perko switch (off, 1, 2, 1+2), but where do outboards, automatic bilge, and all the other accessories and electronics get connected? what is best way to install onboard charger (one or two bank)? I'd like to keep it simple if possible.

Thanks for any advise offered.


----------



## K gonefishin (May 4, 2004)

Do you have a bow mount? If so likely you will need 4 or 5 batteries I would then get a 4 bank or a 3 and a 2.

ducks demise has that boat look him up he may be able to help or Vic’s


----------



## ohiojmj (Apr 16, 2004)

I have Terrova 80ipilot with 2 batteries and a 2 bank charger up front already. Wondering about a 1 or 2 bank charger for the house and oem starting battery in back, plus how to wire it.


----------



## Ranger6 (Dec 27, 2015)

I’ll start with the disclaimer, I am not an electrical expert. If you are looking at running a Perko, Attwood, Blue Sea switch, there are a couple ways to do this. Each boat manufacturer wires their boat a little different so you’ll need to look at your current battery. There will obviously be one big red wire on the battery coming from your motor. Is there another smaller one for all the electrical items on the boat? That wire would go to fuse block or directly to the console to a distribution block. I am a big fan of having a master switch that turns off everything in my boat, in case I leave something on. When I turn my Attwood switch to off nothing in my boat will work, except for the trolling motor which is on separate batteries. So you can wire the switch in a couple different ways.
1. Take the two leads off your current battery, motor and electronics, and put them on the com terminal on the back of the new switch. Run a new red, positive, wire from terminal 1 on the switch to battery 1 and new red, positive, wire from from terminal 2 to battery number 2. Get a new black battery wire and connect the grounds on batteries 1 and 2. This set up will let you chose between batteries 1, 2 and both and it will run everything on your boat no matter what setting you have it on. This will also kill everything on your boat when it’s set to off.
2. Take just the red lead from your motor off of the current battery and put it on the com terminal of the new switch. Run a new red, positive wire from terminal 1 on the switch to battery 1 and a new red, positive wire from the terminal 2 on the switch to battery 2. Run a new black battery wire and connect to the negative on both batteries. This set up will start your motor in any switch setting BUT the electronics on your boat will only work if the switch is set on battery 1 or both. This set up will not allow you to turn off any electronics on your boat either.
I would recommend an onboard charger for all the batteries on the boat.


----------



## firemanmike2127 (Mar 17, 2013)

That's a great explanation by Ranger6. One consideration would be if you have an automatic float switch in your bilge pump. If you plan on docking your boat overnight you might want to consider adding a lead to the provide uninterrupted power to the float switch. Mike


----------



## ohiojmj (Apr 16, 2004)

I think I choose door #1, but has two outboards and 3 or 4 other accessory wires so might utilize pos bus to collect hot wires befoire running to the common on the perko. I will also contemplate the need to run automatic bilge directly to one battery in case I ever park it overnight in a lake. Other than the bilge, I do like to shut everything off to avoid the drained battery (I have experience with this). thanks.


----------



## Ranger6 (Dec 27, 2015)

Great call Mike on the automatic bilge.


----------

