Adding alternator wires. Big-3

Kamilo

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Re: Adding alternator wires. Big-3

There is two skinny wires going to battery directly and one big going through switch. Could i add another switch btw first and 2nd battery before or after ACR I have extra single switch. Here is what i have.image.jpg
 

Kamilo

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Re: Adding alternator wires. Big-3

I dont know much about alternators, but can 2nd battery be switched off while engine is running. Could 105amp alternator overcharge or damage the main deep cycle battery or the alternator regulator is to prevent it from happening?
 

bruceb58

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Re: Adding alternator wires. Big-3

What are the smaller wires for? Normally, you would have those after the switch so they get switched off too. Did you wire these?
 

Kamilo

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Re: Adding alternator wires. Big-3

This wires are original with out switch. I didnt add anything. I would say this is accessory and maybe wire from alternator. Original wires on alternator + and - are 14 gauge. Also the extra battery is 100ah so i would like to try to run single one for now. No bluetop oprima
 

bruceb58

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Re: Adding alternator wires. Big-3

The only wires that should be on the positive battery terminal is the cable going to the switch and a wire to the bilge pump if you have an automatic bilge pump. Everything else should be at the output of the switch or a terminal block.

The output of your alternator should not be connected directly to the battery, It should also be at the output of the switch or connected at the starter. That way, if you alternator shorted to ground for some reason, turning the switch off disconnects power to it.

Your new battery also needs a switch for its loads. That is why I recommend the switch by Blue Seas. It is basically 2 switches inside so you only have to turn one knob.

The one cable with the insulation exposed is not marine cable. It almost looks like house wiring cable because the strands are so big. I would replace that cable immediately before it breaks. Whoever did the wiring of the boat before you did not know what he was doing.
 
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Kamilo

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Re: Adding alternator wires. Big-3

Ok, thicker red from battery will go to switch, switch changed for two way. Extra positive wire from alternator will go to switch as well but should i still need to put acr behind the switch and battery 2? also will get new marine wire connectors.
Thank you!
 

bruceb58

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Re: Adding alternator wires. Big-3

if you get the switch I showed you, you can put the ACR on the output of the switch if you want. That way when you put a dual battery charger to the batteries, the ACRs won't connect.

And change out that thick strand cable.
 
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Kamilo

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Re: Adding alternator wires. Big-3

if you get the switch I showed you, you can put the ACR on the output of the switch if you want. That way when you put a dual battery charger to the batteries, the ACRs won't connect.

And change out that thick strand cable.

Yes i will change that cable terminal. Could you show me on diagram how to connect the acr with batteries and dual banks charger please,
 

bruceb58

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Re: Adding alternator wires. Big-3

Look at the link I showed you.
 

bruceb58

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Re: Adding alternator wires. Big-3

In the second drawing, the top left terminal goes to your house loads(stereo). Your alternator goes to the top right which connects to your engine.

In the second drawing, you can either connect the ACR to the two top terminals or to the batteries themselves.
 
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Kamilo

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Re: Adding alternator wires. Big-3

BTW, they have less expensive ACRs that what you selected.

SI-ACR Automatic Charging Relay - 12/24V DC 120A - Blue Sea Systems

The ACR i got for $70 new in box from my friend. According to the drawing if there is connection btw batteries on a main switch as well on the ACR wouldnt it be that the second battery will be able to draw power from the first battery through the main switch connection?
I have another single switch, couldnt i use it like on this simple drawing and still heve the right result?
Just asking, thank you!image.jpg
 
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bruceb58

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Re: Adding alternator wires. Big-3

Yes, you could use another single switch.

That's a very nice ACR. When you are charging the batteries with the dual charger, you can put the switch in no connect mode to keep the ACR from connecting.
 
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Kamilo

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Re: Adding alternator wires. Big-3

Yes, you could use another single switch.

That's a very nice ACR. When you are charging the batteries with the dual charger, you can put the switch in no connect mode to keep the ACR from connecting.
Great. Thank you for your advices, i will try to battle all that this weekend. Will post some pictures also will fix the battery terminal and move the existing alternator wire to main switch. Thnx!
 
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