Looking for the electrical diagram

[Fred1diver]

I want to understand the charging and starting wiring, I just installed an ACR on my boat but the alternator seems to be wired with the starter, I need it to go to the house bank and is now connected to the start battery because they both share the same wire, I need your help, never played with alternators before, I don’t want to screw it up

[joe_db]

Originally Posted by Fred1diver

I want to understand the charging and starting wiring, I just installed an ACR on my boat but the alternator seems to be wired with the starter, I need it to go to the house bank and is now connected to the start battery because they both share the same wire, I need your help, never played with alternators before, I don’t want to screw it up

This is not real hard, it consists of running a heavy wire from the alternator output to the house battery using an appropriate fuse or circuit breaker. I used #4 wire for mine and a circuit breaker. Mine is probably 100 amps because that is what I had sitting around. Do not skip the fuse/CB, you need a way to disconnect this when working on it, otherwise you have a live heavy wire going straight to the battery.

[Al Schober]

Your confusion stems from your alternator output NOT being connected to the starter - it's connected to one terminal of the starter solenoid, which also happens to be connected to the battery. This connection is often through an A/B switch.
Feel free to connect the alternator to your house bank. You'll need a decent sized cable for both the hot lead and the ground lead back to the engine/alternator. When the house bank comes up to voltage, use can use a VSR to send charge current to the start battery.
If you do ground it to the engine block, I recommend running an additional ground cable from the alternator to the block. Using the pivot bolt for an electrical connection is asking for trouble.

[joe_db]

Originally Posted by Al Schober

Your confusion stems from your alternator output NOT being connected to the starter - it's connected to one terminal of the starter solenoid, which also happens to be connected to the battery. This connection is often through an A/B switch.
Feel free to connect the alternator to your house bank. You'll need a decent sized cable for both the hot lead and the ground lead back to the engine/alternator. When the house bank comes up to voltage, use can use a VSR to send charge current to the start battery.
If you do ground it to the engine block, I recommend running an additional ground cable from the alternator to the block. Using the pivot bolt for an electrical connection is asking for trouble.

Good point! My alternator is isolated ground so it has it's own heavy ground wire which I totally forgot about

[Fred1diver]

Originally Posted by Al Schober

Your confusion stems from your alternator output NOT being connected to the starter - it's connected to one terminal of the starter solenoid, which also happens to be connected to the battery. This connection is often through an A/B switch.
Feel free to connect the alternator to your house bank. You'll need a decent sized cable for both the hot lead and the ground lead back to the engine/alternator. When the house bank comes up to voltage, use can use a VSR to send charge current to the start battery.
If you do ground it to the engine block, I recommend running an additional ground cable from the alternator to the block. Using the pivot bolt for an electrical connection is asking for trouble.

What is a VSR?

[Al Schober]

Voltage Sensitive Relay. It's attached to the house bank, and the relay closes at a certain voltage, sending current to the start battery. Google it and you'll find various manufacturers.

[Fred1diver]

Is it the same as an ACR?
If so I already installed one

[joe_db]

Originally Posted by Fred1diver

Is it the same as an ACR?
If so I already installed one

Yes - same thing. Also called a combiner.