BlueSea Add a Battery

[Tim2Mar]

Vipermax with Honda 225

Have a single battery atm, and would like to add a second battery using the BlueSea Add a Battery kit. (This kit includes an Automatic Charging Relay)

Struggling to find where the +ve Red cable from the new "House" battery should go.

The current red cable from the +ve terminal just disappears down the under deck trunking, emerging in the stern direct to the outboard, so not sure where the +ve to all the nav stuff/lights etc goes.

Would be grateful for any advice.

Attached photo is the layout as it stands

Tim

[GuyC]

Tim

At the moment all your power consumers are powered by the one battery. If the plan is to have an engine battery and a house battery, you will need to separate the engine consumers from the house consumers.

The ACR is simply about the charging and connects the two batteries.

The link below is for the Blue Sea website and shows a few simple wiring diagrams to give you an idea.

The only thing I power from my engine battery is the starter motor and the lift / trim pump but I have a diesel inboard with a stern drive.

https://www.bluesea.com/resources/17...l_Applications

[Tim2Mar]

Thanks Guy for the reply.

I've seen the Bluesea wiring diagrams, my problem is identifying where to connect the +ve cable on the new battery to the house circuit.

I'm possibly overthinking this and am now wondering if I just connect the new battery in parallel that would do?

[GuyC]

Connecting the battery in parallel will just give you one bigger battery. It would give you more capacity but you would still flatten your starter battery if you left a light on or something - it would just take longer to flatten it.

The +ve from the house battery should go to a fuse box, via an isolation switch, which will act as a distribution box for your house consumers.

The +ve from the engine battery will route as previously.

[jwalker]

I'd do it a different way; simply use your second battery as a backup which is always charged by your new charging system. Connect it also battery to battery +ve to +ve via a high current switch which is normally off and -ve to -ve directly. You will know you always will have a fully charged battery should you need it. Just IMHO, of course

[Chanchan168]

I’ve just completed mine. You may only have on and off on your switch and then a combine Incase one battery is too low to start motor. Each side of the switch is separate.

On one side you have the bottom lug which is for one battery and the top side is for either the motor or the house electrics, depending on which battery you wish to operate from. Just repeat on the other side.

When you add the acr relay, you connect each battery from the positive side to each side of the relay but nothing goes to the isolator. Both sides should be fused depending on amps and also needs to be grounded as well. The cable coming from your switch to your house electrics will also need to be fused.

[Chanchan168]

[Tim2Mar]

Thanks JW and Chanchan for your thoughts.

My main confusion is that I cannot see where the existing +ve cable feeds into the "house" side of the boat. I can only see that it comes off the battery, disappears down the trunking, then emerges aft to go to the starter.

Chanchan, I can see that you have two red cables coming out of the top left side of your switch - what is the second cable for?

The boat is new to me, so I am just finding my way around.

[Chanchan168]

Originally Posted by Tim2Mar

Thanks JW and Chanchan for your thoughts.

My main confusion is that I cannot see where the existing +ve cable feeds into the "house" side of the boat. I can only see that it comes off the battery, disappears down the trunking, then emerges aft to go to the starter.

Chanchan, I can see that you have two red cables coming out of the top left side of your switch - what is the second cable for?

The boat is new to me, so I am just finding my way around.

On the left hand side of my switch I have the start battery on the bottom lug with the engine start lead and engine fuse box lead coming out of the top.

On the right hand side of the switch I have the house battery lead coming in from the bottom and the house electrics lead coming out of the top going to the console. That lead is also fused at the console.


The acr is fed by both batteries +ve but doesn’t go anywhere into the switch.

[Bobg]

Work backwards from your fuse panel. There should be one thick +'ve cable (maybe coloured red) from the fuse box, which will go back towards your single battery. Either at the battery terminal or a stud embedded somewhere in your trunking system, or isolation switch.. The cable to the starter will also be there. Now separate the cables and wire it as per the Blue Sea diagram.
If you have the 'Add A battery' kit, replace any existing isolator with the one supplied.

[breezeblock]

your layout as it is just now is probably inadequate for what you are starting you should have went for the bigger master switch as chanchan has in his set up I don't think the master switch is rated for the start current of your big honda remember and fuse your battery charging relay as well with a fuse thats bigger than the max capacity of your alternator the blue sea stuff is pretty well explained in the circuit diagrams the master switch is 2 parallel circuits for the + side and theres a common link when its in the second position have one side for the main start for the engine and the other side for everything else

[Bobg]

The manual for your engine will quote the cranking current for your starter motor. Somewhere in the region of 400A plus. The standard AddABattery switch is rated about 450A, I think? (look at the spec for the isolater) If your starter current is greater than that, then you will need a larger switch, but with the same contact configuration. I e it will have 4 large studs and three switch positions. On Off and Both. The spec will also give you an indication of the largest engine size the isolator can cope with.

[Tim2Mar]

Thanks Bobg and breezeblock for your input.

I will take your suggestion Bobg of tracing back from the fuse box and see if I can find the elusive +ve cable that way.

Breezeblock, I have actually got the same Bluesea kit as chanchan - the switch is rated 1000A for 10seconds, and the Honda Bf225a needs a battery that can deliver 800 Cold Cranking Amps. I take your point (along with other contributors) about using proper fuses in the right places, and will sketch it all out before I do any hard wiring and submit for comments.

Many thanks to everyone for all your suggestions.

[Chanchan168]

Good luck, and don’t be afraid to post back if you need assistance. This forum is a valuable source of expertise and experience

[breezeblock]

Originally Posted by Tim2Mar

Thanks Bobg and breezeblock for your input.

I will take your suggestion Bobg of tracing back from the fuse box and see if I can find the elusive +ve cable that way.

Breezeblock, I have actually got the same Bluesea kit as chanchan - the switch is rated 1000A for 10seconds, and the Honda Bf225a needs a battery that can deliver 800 Cold Cranking Amps. I take your point (along with other contributors) about using proper fuses in the right places, and will sketch it all out before I do any hard wiring and submit for comments.

Many thanks to everyone for all your suggestions.

the bottom of your picture looked like the small master switch that blue sea or bep make my apologies there is an excellent wring diagram that comes with it use it there should also be a wire run to the start circuit as well to knock out the charge relay during starting

[Tim2Mar]

breezeblock - yes the photo is how the system is wired now, and the switch I think is, as you say, a bep.

[breezeblock]

Originally Posted by Tim2Mar

breezeblock - yes the photo is how the system is wired now, and the switch I think is, as you say, a bep.

heres the proper diagram https://www.google.com/url?sa=i&rct=...50605320326774

[Tim2Mar]

Quick Update
Managed to find the power supply to the House Circuit (Many thanks to my chum BOG) and have worked out where everything goes. Almost. Turned out that the pink cable from the +ve battery terminal in my original picture was divided near the switch panel, one branch to the bilge pump, the other to the rest of the switch panel.

Is it safe to assume that although the Blue Sea wiring diagram shows both -ve cables going to the -ve Bus Bar, I will achieve the same effect by cabling the two -ve battery terminals together?
And secondly, the fuse between the switch and the House Circuit should be rated to cope with whatever equipment (lights, nav, etc) I am using?