Considering adding a 2nd battery to my SX-230 HO

[aznomad]

I just finished reading all of the relevant threads regarding 2nd batteries but have a couple questions I could not find answers to......

It appears that the majority of people added a 2nd or 3rd battery because of high power consumption from accessories ~ amps, subwoofers, lighting, etc. My reasons for adding a 2nd battery are simple...... sometimes we float down the river in Parker AZ and listen to our stereo. We don't have power amps or subwoofers, we just want to float and listen to music for an hour or two. I have never had a problem with my single battery setup. I am just trying to be a little proactive.

1. With that being the case, do I really need a setup with separate starting and house battery isolation relays like the ACR?
2. Would I be making a terrible mistake to just hook-up the 2nd battery in parallel with the first?
3. Since I would only be pulling the same amount of charge for the 2 batteries, but perhaps for a longer period of time, shouldn't my factory charging setup be fine?
4. My current battery is located on the aft/port side ~ for balance purposes, would it really matter if I added the 2nd battery adjacent to the 1st or should I add the 2nd battery on the aft/ starboard side?

Thanks for the feedback

 

[Beachbummer]

I have the 2 batteries on your same boat spec. The previous owner set it up, but I would have done the same with what I know now. Another battery and a multi switch. No ACR. I generally set it to one battery or the other. But try to avoid ever leaving it on both. That way if the battery drains down, I have my backup on the other battery.

 

[Beachbummer]

And, what you asked:

1. No. If you manage your switch you won't need the ACR, and with the switch you constantly test your redundancy.
2. Same as #1. Not a terrible mistake, but a missed opportunity for redundancy that the switch will bring.The reason you don't want the battery in parallel is that you gain nothing vs replacement with a bigger battery. When it drains you are still stuck.
3. Factory will provide charge no issues with your usage.
4.I would leave the battery close to the other one. those cable carry a lot of current I would leave as short as reasonable. If you did that I would recommend a large breaker close to the far away battery. maybe 100 amps?

 

[aznomad]

Thank you for the detailed reply. I understand everything you have said. My boat is in my truck garage a few miles away so I don't have ready reference ~ but, there is a red switch on the aft firewall of the battery compartment. I never payed much attention but my assumption was that the switch was just an isolation switch for storage. Do you know if the red switch is factory or would you say it was an add-on? I can go over later today to see if it is a two position switch (on/off) or 3 position which I assume would be battery [HASH=108]#1,[/HASH] battery [HASH=15]#2,[/HASH] and off.

I understand the current draw and amperage drop from the large wire run if I separate the batteries. After reading your thoughts I will locate the batteries adjacent to one another. If my existing switch is factory and if it wasn't designed for multi battery use ~ do you have a recommendation for a replacement switch?

 

[Beachbummer]

Perko is a well known maker of marine switches, they have made them for years and years. The pricing is pretty aggressive. I think you can't buy a bad one.

I have a similar red switch, but my second battery tray does not look factory. An original owner will have to answer that. I can't tell if this was a factory option or installed after the fact.

 

[aznomad]

I found quite a few multi functional cutoff switches on Amazon Prime and the prices range from $13 to about $22. Some have about 750 reviews and still 4.6 positive. I feel I would be safe with a switch with such a high rating. Wiring the switch will be no problem for me.

 

[Beachbummer]

I have a hard time advocating against the cheaper switch, but the difference is only $20. If you plan to keep your boat more than 5 years I would consider the Perko, but I'm struggling here, because generally I am cheap cheap cheap.

 

[bronze_10]

I have two bats in my sx230... I try to remember to have both batteries on while we are cruising so they will charge.. then switch tone on bayktt while floating.

 

[aznomad]

UPDATE: I looked at the disconnect switch on the boat. It appears to be factory installed, very heavy duty, and only has two positions - on and off.
I will leave it as wired for a main disconnect, but install a new (additional) one that allows me to selectively select one battery or the other ~ or both.

 

[Beachbummer]

That sounds like 2 places for stuff to break. I would ensure you are getting the benefit you are expecting. Might work out just fine, just a thought.