New Boat, Want to add a battery switch

Another person lookign for tips on how to wire up my boat to two batteries and a switch.

I have read about it , and had a switch already installed on my old boat. I just want to make sure I have my head wrapped around it completely before I tackle the installation.

I would also like to add a volt gauge while I'm at it, as the boat doesnt have one right now.

Its a 2005 Center console proline.

I attached pictures of a 30amp fuse panel? and positive and negitave terminals in the back of the boat and behind the helm.

Right now the boat just always has power. which is nice to be able to trim the motor up and down with out having to climb in and turning the switch on.

Is there a way to keep the trim system hard wired? and have the rest of the boat off the battery switch?

Do I simply take the power and ground cables that are on the one battery now,a nd attach them to the switch, and then add two battery cables to the spots on the swtich?

Thanks...

Re: New Boat, Want to add a battery switch

1) You can leave power active for the trim/tilt system but you need to find the +12 volt feed for that system and connect that directly to one of the two batteries

2) You DO NOT connect a ground wire to the switch. It is acceptable to add a switch in the ground side of any electrical system but you do not mix positive and negative connections on the switch. It is recommended that you always switch the positive side.

3) Here is a diagram of how the switch is configured. What is not shown in the diagram is the feed to the fuse panel. The positive feed to the panel should be connected to the COM terminal on the switch. This provides the utmost flexibility of this system. You can start the engine from either or both batteries, you can charge either or both batteries, and you can run all accessories from either or both battiers -- all depending on how you have the switch set. OFF is obviously off and kills all power except in your case, for the trim and an automatic bilge pump if you have one which would be connected directly to one of the batteries (typically the house battery since it would typically be a deep cycle.)

Re: New Boat, Want to add a battery switch

Silvertip! thanks for the quick and really good reply!

So the positive feed for the panel is the red wire coming out of the bottom of the panel? Just connect that to the COM on the switch and set up the batteries as you showed me?

Thanks again!

Re: New Boat, Want to add a battery switch

I cannot verify that the red wire off the panel is the main feed to the panel. Only you can do that. If it is -- then yes, move that wire to the COM terminal. Nothing else needs to change except for the positive cable going to the engine. That moves to the COM terminal as well. The tilt/trim and bilge pump are direct wire as you desire. You need to connect the negative terminals on both batteries together as shown.

Re: New Boat, Want to add a battery switch

Other things to consider...

Once you get it wired up, remember, only the battery that is selected is going to be charged.
When running select BOTH to charge both. There are relays that do this automatically.
When Stopped, Select one and keep the other for restarting.

When running, If selecting #1 or #2 turn the knob past BOTH to make the change.
Example... #1 > BOTH > #2 > BOTH > #1

Do NOT Select OFF when the engine is running.
Example... #1 > OFF > #2 > OFF > #1

Some alternators will vent the "Magic Blue Smoke" if operated without a battery attached.
Some switches have extra terminals to protect the alternator.

Re: New Boat, Want to add a battery switch

Thanks for the info guys! I am trying to get all the info and parts I need, and then on a warm day brush the snow off the boat and get to it...

I am going to look into that relay, it would be nice to have it switch by itself when running, so that I know both batteries are always goin to get topped up...

Re: New Boat, Want to add a battery switch

That relay is called and ACR (automatic charge relay). One battery is designated "primary" which typically would be the main starting battery. The other is the auxiliary. In operation, the primary battery is always charged first and the auxiliary is then switched on line for charging. The disadvantage of an ACR is that unless it has a "combine" function, you cannot start the engine from the second battery. The other disadvantage is the accessories must all be powered from the auxiliary battery. Again limiting use of the start for for that purpose if needed (unless again the ACR has a combine function). A dual battery switch is cheap, reliable, and probably the most versatile way to incorporate a dual battery system. If you are switch "challenged" then the ACR is a good alternative.

Re: New Boat, Want to add a battery switch

I would never put an ACR on without a switch. The ACR is there to help you charge both batteries without having to turn the switch to the "Both" position. You also never start an engine with an ACR in a "combine" state. The ACRs are not rated for that type of current.

I would buy this:
http://bluesea.com/category/78/1/productline/overview/329
Switch and the ACR

Re: New Boat, Want to add a battery switch

bruceb58 said:

I would never put an ACR on without a switch. The ACR is there to help you charge both batteries without having to turn the switch to the "Both" position. You also never start an engine with an ACR in a "combine" state. The ACRs are not rated for that type of current.

I would buy this:
http://bluesea.com/category/78/1/productline/overview/329
Switch and the ACR

Click to expand...

I'm no expert by any means...but this has been a great mod to my boat and it isn't too difficult to install. Call around to get the best price on the extra battery cables you will need.

Re: New Boat, Want to add a battery switch

flsooner said:

I'm no expert by any means...but this has been a great mod to my boat and it isn't too difficult to install. Call around to get the best price on the extra battery cables you will need.

Click to expand...

genuinedealz on ebay is the guy that many on here buy cables from. Has good prices and good service for custom made cables.

http://genuinedealz.com/

I would not have a dual battery settup without an ACR on it in addition to a switch.