Wiring power to new stereo and adding second battery

[AstrongBoat22]

Hey Boating Electricians,

Last summer I purchased a 1998 Chaparral 1930ss. I am in the process of installing a new Fusion MSra70 head unit and four kicker speakers. As of now, I have all of the speakers wired to the head unit harness (replaced all speaker wire with higher quality wire), but have not run new ground and power (+12v) wires. To power the radio, I will be adding a second battery (deep cycle). I was hoping someone could provide advice on the best way to wire the head unit to the new batteries while also installing the dual battery configuration. I have researched the Blue Seas system and think that will work for the dual battery configuration, but how do I incorporate the stereo power into the new battery setup? Will I simply just run the ground wire to the negative terminal on the deep cycle and the power wire to the + terminal, then add the dual battery system? Or do i need to go through some sort of grounding/circuit breaker to run the head unit power? I found a couple of distribution blocks during the install (i think that's what they are), but they are all connected to the current single battery configuration so i am not sure if i should be using them.

To test the head unit and speakers, I ran a quick connection straight from the ground wire and +12v wire to the single standing deep cycle battery (batteries are not connected yet). The speakers sound great. They are the KM6.5, which have incorporated LED lighting. I have also wired the LED lights to a remote and ran a quick connect to the deep cycle battery for testing.. they work great also. I am also seeking advice on how to incorporate the LED power to the new battery system.

I have plenty of 8 gauge wire to run the head unit ground and power wires. I have 16 gauge wire for LED power if i need it.

Below are random pictures I took during the first part of the install. They probably won't be all that helpful for my question..but I know people on here like pictures, so why not!



Poor man's soldering station.



New boys installed (right cockpit)


Left cockpit

 

[dingbat]

I hunk your getting a bit ahead of yourself.

What is the current drain of the radio?
Doubt its enough to justify buying and installing a switch and a separate battery to support it?

How big is the deep cycle battery?
How are you going to charge it?

You would probably be better off to install an ACR and wire your “house” loads to the deep cycle leaving the other battery for starting purposes only.

 

[AstrongBoat22]

Dingbat - thanks for the response.

The deep cycle is the generic everstart 12V group27 750MCA. I can charge it with a maintainer, but i'd rather not if there is a way to rig this up without having to use a charger.

"You would probably be better off to install an ACR and wire your “house” loads to the deep cycle leaving the other battery for starting purposes only."

^This pretty much sounds like what i would prefer to do. Is it as easy as wiring the stereo ground/power to the Deep cycle and rigging that up to the starter battery with an ACR for charging?

 

[KD4UPL]

You can wire your stereo directly to your second battery using a proper fuse or circuit breaker as near as possible to the positive battery terminal. You can use an ACR to keep the stereo battery charged when the engine is running.
Or, you can connect your stereo to the existing buss bars in your boat and install a battery switch. Then you can select between running everything in the boat from either battery 1 or battery 2. You can also select both to charge both batteries when running. Or you can use the ACR to keep both batteries charged and still select between 1 and 2 with the switch.
I use a battery switch but I haven't spent the money on the ACR yet. I use 1 battery on one trip and the next time I use the other battery. If I'm going to be running the boat at cruising speed for a long time I might put the switch in BOTH to give them both a good charge.
With this set up, if I kill the battery running the stereo with the engine off I can just switch to the other one to start the boat. Or, if one battery goes bad, I can run on the other one.

 

[dingbat]

Dingbat - thanks for the response.

The deep cycle is the generic everstart 12V group27 750MCA. I can charge it with a maintainer, but i'd rather not if there is a way to rig this up without having to use a charger.

"You would probably be better off to install an ACR and wire your “house” loads to the deep cycle leaving the other battery for starting purposes only."

^This pretty much sounds like what i would prefer to do. Is it as easy as wiring the stereo ground/power to the Deep cycle and rigging that up to the starter battery with an ACR for charging?

ACR is design to isolation the “house” load from the starting system. The ACR will not charge the “house” battery until the “start” battery is fully charged.

To accommodate, you need to move the “house” loads from the “starting” battery over to the “house” battery. If not, the starting battery may never get full and the house battery will never get charged.

Then there is the issue of charging the battery. Having a lot of battery in reserve is good, but only if the charge can be fully renewed between trips.

Nothing kills batteries quicker than leaving them in a state of discharge for periods at a time.
A maintainer does not have the output to properly charge a grp. 27 deep cycle between trips.

It all boils down to the following:

What is the output of your motor’s charging system? How long do you run the motor after the fact?
How do you make up for a shortage?

Most boaters don't run their boats long enough to fully charge one battery between trips, let alone two.

 

[AstrongBoat22]

Thanks guys, this was very helpful. I am going to move all of my house loads over to the deep cycle battery and run an ACR between the house and starting battery. I might install a switch, but at the end of the day i am trying to protect the starting battery from dying and i believe the ACR will do that. I have a 25amp agu fuse (to protect the stereo) that i will run on the stereo power line and i will mount it as close to the battery as possible.

As for keeping the deep cycle charged. I am going to calculate the output of the alternator vs the drain of my house loads the best I can. In all reality, the deep cycle battery charge will be trial and error until I really figure out what i need to keep the house loads powered based on how I utilize the boat. If all else fails, my brother stores his bass boat with mine and he has a charging setup that I can use to keep the deep cycle topped off. I trailer my boat, so i can top it off with the charger all summer if i really need to.

I'll post more pictures of the install once it is complete.