I just installed the blue sea 7610. I cant say how well it will work yet but I can vouch for there custemer service. I called them about some questions and was talking to a tech in less then a minute and they knew there product and are very pleasent to talk to.

Hello.

I invented the Combiner in 1993. We sold them through West Marine until our contract was terminated. Our primary retailer now is Defender. There have since been a number of copies. We are a small company with a limited number of products so we can't compete with the Blue Seas advertising level but our overhead is low and service is better.

With over 30,000 Combiners out in the field for as long as 15 years and ALL ON UNCONDITIONAL WARRANTY, we only get about 8 returns a year, of which typically 75% have nothing wrong with them. So far only one return this year.

Interesting.

Here's a newbie question.
Why would you have a system to combine the batteries and a switch to separate them, when the same switch has a combining setting?

??

The Yandina combiner (at least the model I saw) cannot pass enough current to start an engine from the opposite battery, so that is one reason to have an A-B switch. If the switch is wired in the conventional manner, when put in the Both position, it allows both batteries to crank an engine.

At least one of the Blue Sea combiners can pass enough current to start an engine, so you could technically do without the switch, but most boaters like a disconnect switch for winter storage (most A-B switches include a disconnect position).

Also, the primary purpose of the combiner is to charge two batteries with one charger - such as an alternator when you only have a single engine. Prior to combiners, isolators were used, and they were not really all that good. The combiner automatically connects both batteries when it senses the alternator is charging, and automatically disconnects both batteries when the engine shuts down.

This automatic connect-disconnect feature is the real advantage of the combiner. While you could do this manually by flipping the A-B switch, if you leave it in the both position when the engine is off - which would be required to charge both batteries simultaneously - can also discharge both batteries simultaneously.

The switch that comes with the Blue Sea Systems 'Add a battery' package is not an A/B switch. It has three settings, Off, On (which isolates starting and house systems in the absence of a charging source), and Combine. AFIK, if the starting battery is low, and no charging source is present, the 7610 ACR will not automagically combine the batteries. One would have to manually switch to Combine to start the engine from the House battery (or more accurately, both batteries). I expect in most situations it'd be the the House battery that would be depleted as the starting battery is effectively isolated, but stuff happens. I'm in the habit of leaving my switch set to On, and would only use combine in an emergency.

Al, you are absolutely right about that. Fortunately, I've never had the starting battery fail, since everything else on my boat goes through the house battery except the starter and the bilge pump.

If it failed, I would have to take 10 minutes and swap the house battery with the starting battery.

One of the projects I need to do on the boat is to upgrade the battery wiring. The alternators on both engines are tied together, then to a single A-Both-B switch, and then to two batteries.

So even with two engines, I still have the problem with leaving the switch in the both position. This was the factory setup, and I am not all that happy with it.

I plan on upgrading it someday, and when I do - I want to separate each engine with its own battery, and adding a third battery for a house bank. I will for sure be adding a combiner; probably two of them, and a couple of A-B switches.

Its just not yet been a priority.

Two people I boat with had one of two of their new batteries die on them after only 3 years. I mixture of leaving the switch on both and/or using mostly the same battery.

Since most new boats comes with a switch (including mine), getting a combiner was a must upgrade for me.

I did a Bluesea Systems Add-a-battery project last summer. Here is the link to my install. The pics seem to have disapeared but might still be helpful if you go that route.

-- Bob

Add A Battery Project

You gotta revive those pics - that was one heck of an install.

Thanks Jim_R

I was able to find the pics but need to get them up on my website. We are so busy trying (read detailing boat, etc.) to get to the lake house that it will have to wait a few more days but I will get r' done.

BTW - I completed my follow-on stereo install project with Alpine amps & headunit, wired & wireless remotes, XM radio and Wet Sounds tower speakers. I will write this up as well.

-- Bob

Where can you purchase this one?

Where can you purchase this one?

Here is the revived version of my original post

Add-A-Battery Project w/ Pics - Revived