Blue Seas dual battery set up and acr

[Aaren22]

Has anyone installed the Blue seas dual battery switch and ACR on their boat? I have a 2001 SAN and I'm not sure if I connect the top 2 side of the switch to the starter or it looks like the starter goes to a relay.....

[MLA]

The starter is originally connected to the battery. The new switch is going between the starter and battery. Check with the retailer you purchased from, they may be able to assist with a custom diagram thats more specific to your boat. That diagram is not the only ( and not the best) way to wire that system up.

[functionoverfashion]

The starter is originally connected to the battery. The new switch is going between the starter and battery. Check with the retailer you purchased from, they may be able to assist with a custom diagram thats more specific to your boat. That diagram is not the only ( and not the best) way to wire that system up.

Exactly. Are you just adding the switch to have a backup battery for emergencies? Or are you using one for accessories and the other for starting? There are many ways to add a battery to your system.

When you're in your boat looking at the battery as it is now, how many wires go to the positive terminal?

[peteSki]

Exactly. Are you just adding the switch to have a backup battery for emergencies? Or are you using one for accessories and the other for starting? There are many ways to add a battery to your system.

When you're in your boat looking at the battery as it is now, how many wires go to the positive terminal?

I installed this a couple years ago, but as above it will depend on how you plan on using your batteries. In my case, I wanted to keep my second battery isolated from the first battery which was designated for starting the boat, and the second battery to run the high powered accessories like the stereo. I used the diagram you included but left out the battery switch completely. It limits me in that I can't choose which battery to select for accessories or start, but that didn't matter to me. I installed a small fuse panel for the accessory battery and rewired the stereo and a couple other things to it. The ACR has been working fantastic with no issues for the past 2 years so I'm really happy with it. This past winter I added a simple bypass switch that when closed connects the 2 positive terminals of the ACR, effectively forcing both batteries to be in parallel regardless of their charge state. I installed this as an emergency feature only, meaning that if I was ever out on the lake and the main starting battery were to go down and I couldn't start, I could use this switch to connect the batteries and start off the second battery. This wasn't super important to me since where I boat I'm usually quite close to shore and help, but if it's important to you you may consider adding in the correct battery switch as above.

The wire that appears to go from the starter to the relay is for the start isolation feature on the ACR. When the starter gets power to then crank the engine, this wire tells the ACR to isolate the 2 batteries so that the load for engine start comes from only 1 battery, not between 2 of them. This wire does not carry the current that the starter needs, so it's low current as it only senses that the starter is running. Once the starter is done and the engine is running, the ACR can then combine the batteries assuming the alternator is working and your main battery is sufficiently charged.

Hope that helps.

[hal2814]

In my old boat I also left out the Perko manual switch. It was also set up to run one battery for starting and the other for accessories. My thought was if there was an emergency and I needed the second battery for starting, I could just swap them on the water in a few minutes. If your batteries aren’t real accessible while underway, a manual switch may be worth it.
so I ran + on battery 1 to A of the Blue Sea and + on battery 2 to B and to a fuse panel for accessory power. The rest followed the above diagram.

[MLA]

This past winter I added a simple bypass switch that when closed connects the 2 positive terminals of the ACR, effectively forcing both batteries to be in parallel regardless of their charge state. I installed this as an emergency feature only, meaning that if I was ever out on the lake and the main starting battery were to go down and I couldn't start,

Im guessing you did not realize that the ON/OFF/COMBINE battery switch already does this? It does it without the excessive starter draw passing through the ACR, which its not rated for, like in your scenario.

[functionoverfashion]

I added a simple bypass switch that when closed connects the 2 positive terminals of the ACR,

I'm guessing this switch is in parallel to the ACR - one cable connected to each terminal with the switch in the middle - so that when the switch is ON, current would be able to flow through the switch, as opposed to somehow forcing the ACR to close and allowing the starting current to flow through it. Basically instead of connecting the switch to the batteries with its own cables, it just connects to either side of the ACR and bypasses that relay to combine the batteries if needed.

[peteSki]

I'm guessing this switch is in parallel to the ACR - one cable connected to each terminal with the switch in the middle - so that when the switch is ON, current would be able to flow through the switch, as opposed to somehow forcing the ACR to close and allowing the starting current to flow through it. Basically instead of connecting the switch to the batteries with its own cables, it just connects to either side of the ACR and bypasses that relay to combine the batteries if needed.

Yep, that's exactly what I did. The bypass switch is close to the ACR and connects either side. Not the ideal setup for starting, but for me it's really just a simple last resort and piece of mind to have. Due to the second battery location, it would be a pain to simply jump the batteries with cables while on the water. The switch I got is also much smaller than the typical Perko ones, so it takes up less space and I was able to mount it somewhere inconspicuous, but reachable.

[Aaren22]

I have everything wired up I just wasn't sure where the top #2 terminal wire went. The diagram shows it going to an outboard motor so I wasn't sure if it went to the starter on the gt-40 or to the alternator possibly?

[MLA]

I have everything wired up I just wasn't sure where the top #2 terminal wire went. The diagram shows it going to an outboard motor so I wasn't sure if it went to the starter on the gt-40 or to the alternator possibly?

It depends on whats wired to the bottom #2. Alternator is likely wired direct to starter, rather then have its own lead at battery.

The cable in question, where did it come off of? Knowing what the cable does or goes, makes it easier to determine which post of the switch it is best connected to.

[Aaren22]

Bottom #2 is my starter battery.... I have everything wired just like the diagram with the exception of a few accessory wires