Power source for two amps

C

CapJB

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Jan 22, 2021
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Hey new to marine audio when it comes to having two batteries with a battery switch.My question is where to get the power for two amps so that I’m not just running on one battery or is that the best way to run it or can i run it off the switch so it will run off the battery my switch is set to.
 
alldodge

alldodge

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You "can" have two Bats and run off one, switch to the other for audio when motor is OFF, but would not suggest doing that

Run motor as before
Install radio and amp and connect it to the second Bat

Add a ACR so the motor will charge the start and stereo (amp) Bats when running. When motor stops it will automatically disconnect from the start Bat. Only need to place switch on BOTH when unable to start motor

Don't know if you have a OB, IB or I/O
Use the house Bat as the Amp source or anything else you want to run and not have it effect the start BatTwo Bat one switch and ACR.jpg
 
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CapJB

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I have an I/O but I think I get it but what what position would I run my battery switch it shows it as in the off position in the diagram is that correct.
 
alldodge

alldodge

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No, off position is when boat is stopped, motor off, on the trailer or at the dock. The pic is just a pic

Position 1 is normally the Start Bat
Position 2 is normally the House Bat

If you install an ACR then just leave in Position 1, the ACR will charge both Bats when motor is running

If your not installing an ACR, then place in position 1 and start motor. Once running switch to Both (could be labeled 1+2) and this will change both. Once motor stops, place switch to position 2 for amp.

Do not move switch to OFF at anytime while the motor is running, it can blow the alternator
 
dingbat

dingbat

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alldodge said:
Once running switch to Both (could be labeled 1+2) and this will change both.
Click to expand...
It may charge both....but it will certainly equalize the charge in both batteries.

A shorted cell in one battery kills both
 
sam am I

sam am I

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alldodge said:
Once running switch to Both (could be labeled 1+2) and this will change both.
dingbat said:
It may charge both....but it will certainly equalize the charge in both batteries.
Click to expand...
Click to expand...
As does happen each time the ACR "automatically" switches on.

When switched on, the ACR is just an "automatic" 1+2(both) , no diff electrically with a human's switching over the batt switch to 1+2(both), parallel path, same result............
 
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sam am I

sam am I

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CapJB said:
My question is where to get the power for two amps so that I’m not just running on one battery or is that the best way to run it or can i run it off the switch so it will run off the battery my switch is set to.
Click to expand...
Most likely you already have a Off, 1, 1+2, 2 switch/setup....w or w/o ACR, doesn't matter

Just using headphones here would be best IMO!

BUT, you can just add a 40 amp'ish **DPDT relay wired(see attachment) such that with the Ig. on (motor running) both amps will have their own battery (better for dynamically loading), then, with Ig. off (motor stopped) the relay will switch over both amps to JUST the house batt (save start batt for starting).

** or use 2 SPDT equivalently wired
 

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dingbat

dingbat

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sam am I said:
As does happen each time the ACR "automatically" switches on.

When switched on, the ACR is just an "automatic" 1+2(both) , no diff electrically with a human's switching over the batt switch to 1+2(both), parallel path, same result............
Click to expand...
Except the ACR will not connect if the “charge” battery drops below the under voltage lockout of 12.7
No such protection with a manual switch
 
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sam am I

sam am I

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dingbat said:
Except the ACR will not connect if the “charge” battery drops below the under voltage lockout of 12.7
No such protection with a manual switch
Click to expand...
Neither do/did I and sure there is, just don't manually switch it to 1+2 till ya see the voltage gauge(I usually watch my gauges) up around 14V. If the gauge drops below 12'ish when in 1+2, turn it back to 1, wait little longer or if it keeps doing it, investigate for a short cell.....

Like I said, no difference electrically, one is just an automatic(threshold driven, yes) 1+2 switch in parallel with the human's manual 1+2 positioning of a switch........When the ACR is on and STAYS on, and just as the manual switch does, the battery's become obviously hard wired together in parallel, therefor must equalize, again, just as it will/did/does with the manual switch.

Now, I would admit, the auto feature of it(ACR) going to "1"(off) from "1+2"(on) when the key is off is nice, when I didn't have a charge manager and only had the a batt switch, I differently forgot 1/2 the time, but when I was camping/extended trolling and such, I never forgot.
 
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djnordeen

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I have a volvo penta 3.0L I am assuming I have a 60 amp alternator. I have to verify, but what I see as parts replacement is 60 amps.
 
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