adding 3rd battery

I've done a few searches and couldn't quite find what I was looking for. I currently have a 2 battery setup with a Perko 1-2-Both switch. I'm wanting to increase engine off play time, so I think adding a 3rd battery is the answer. I was thinking of doing one of the kinetiks, as well as adding one of their onboard power supplies to plug in at night.

What would be the best way to hook this up? I first thought just Parallel it to the #2 battery (#1 is the starting battery), but for charging reasons and the difference in battery type I don't think this is a good option.

Thanks

You are correct. If you want to parralel two or more batteries you should buy 2 similar style batteries. What type of battery do you have now on the starting side and auxiallary side?

I'll have to check what exactly they are. The end goal is to have those two stock batteries for starting, etc, then have a bank of 2 or 3 kinetiks dedicated to the stereo system.

IMHO, you probably only need one backup starting battery. Then if you want to run another bank fine. Just use exact same batteries hooked in paralell. If you are running a big system, I would just charge the starting and stero bank separately before going out. I put my perko to off then charge them separately. I don't use a automatic separator because if you run your stereo bank to dead while partying you don't want your alternator trying to charge up two or 3 kineticks because it will fry your alternator. So manually switching to 2, to get home is a better way to go. If you leave your boat on the water you may need to upgrade your charging system.

so.. the alternator will only provide charge to the battery that the Perko is selected to? For example.. #1 is my starting battery, and #2 is 3 kinetiks in parallel.. I start the boat with #1 and ride with the stereo/engine running on #1. In this case the alternator provides the output to the stereo, and any output above 90amps is depleting my #1 battery supply. In the cove, I would switch to #2 (the 3 kinetiks) and play until the batteries are dead, switch to #1 to start the boat and head in. My alternator should be protected as long as the boat is not running with the Perko selected to #2.

Am I understanding this correctly?

No.

On positon #1 all alt output goes to batt#1 ( assuming your HU/amps are hooked up to batt bank #2)Is your HU still hooked to batt#1? Most people forget about this.

Are all 4 of your batt's the same kind ( flodded, AGM, gel)?

Your setup is not ideal, but here's what I woudl do. Make sure all batt's are fully charged to begin with, start on both, then when you get to the cove, switch to #1 ( isolating yrou two banks, and will allow you to start on #1)

Make sure there is no draw of your starting battery while runnign yrou stereo.

I still like the idea of hookign everything ( stereo, boat electronics, ect) up to one bank of batteries and having a second battery hooked up ( thru perko switch) as emergency only.

I don't have this setup.. this is what I am wanting to upgrade to. Why is it not ideal? What would you suggest.

I am worried about my alternator attempting to charge 3 power cells.. as long as the perko is not selected to that bank with the engine running (and the batteries decharged) then I shouldn't have a problem..correct?

"I am worried about my alternator attempting to charge 3 power cells.. as long as the perko is not selected to that bank with the engine running (and the batteries decharged) then I shouldn't have a problem..correct?"

Correct.


Make sure all 4 batt's are same type ( AGM, Gel, flooded---reason= they charge at different rates.) Unless you have an unorthodox mounting location/postion, AGM/Gell batts, are not worth the $$$ ( when comparing amp hours to $$). I've been using 6V batt's ( Trojan t-105's) same pair for 4 years, no issues, still hold a full charge. hair over 3k RMS system.

Your amp stock is 90 amp( closer to 100-105 amp max)( assuming it's the 08 wakesetter).

How big is your stereo?

IF your batt's get run down real low it's best to not let the alt try and charge them...your alt is not a battery charger...more of a maintainer.

PS. I see your in Houston. I live on Lake Houston. There's no stereo shop in Houston that knows much about boat stereo electrcial/charging. Texas stereo probably has the best understanding...they used to run dual alts in boats. Most shops use their car knowledege....2 diff. animals.

another option is a batt. combiner.

hmmm never thought of that. I have an 07 malibu LSV and now I'm thinking I better check if my head unit come off my starting battery. Overall just the H/U does not pull much power but I want my back up totally unused until I switch my perko thx for the heads up