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Random Quote: Life sure has it's share of disadvantages, but it still beats the hell out of the alternatives
My previous boat had shorepower and a huge house bank. I have now downsized to a boat with a single outboard, two batteries, and no more shorepower. Because of this, I now want to ensure that both batteries get charged, both batteries never get discharged together, and don't want to remember to switch the battery switch back and forth. #1 out and #2 back will not work for me for multiple reasons (non symmetrical trip, different batteries for house and starting, all electronics on batt 2, etc).
This leaves me with either a battery combiner or using the 2nd charging wire from the outboard, a 2008 200hp Etec HO. If both options are available, and both would cost about the same (~$100) which would make more sense and why?
great question...the only advantage I can see is that a shore charger hooked to one would charge all of them...other than that, I think it's a toss up.
But a BEP module would give you switches, emer paralell and combiner all in one....I'll always go that way.
I had two Optima Blue Top house batteries installed in my Parker Pilothouse that handle all electronics plus my fwd bilge pump. My Yamaha F150s each have a 2nd charging output. I simply had my rigger run a charging line from one of the motors to a 1-2-both bat switch and to the batteries. I also had a 2-bank charger installed to keep them charged when I'm working at the dock. It has worked flawlessly for the last 2 yrs, and is very simple...........I like simple.
I have looked at the Blue Seas battery combiner, but I was curious if you have the option for a second charging circuit of the engine, how does a battery combiner compare to using the 2nd charging wire?
Do I need to worry about the contacts welding together on a battery combiner and my batteries stay linked together? Will the battery combiner disconnect the batteries if one of them is too low? What are the disadvantages of using the auxiliary charging circuit if an outboard is supplied with one? I am talking about a single engine, dual battery setup, with no shorepower and no battery charger.
If the price is similar, why would I go for buying a combiner over a wiring harness or vice versa? I still have the emergency parallel by moving the battery switch to "all", but normally the switch would stay on 1, which is the starting battery. All of the electronics would be hooked up to battery 2. Then, with either a battery combiner or using the 2nd charging wire off the engine, I would be able to charge both batteries, but the electronics would only discharge battery 2.
I'm sure I'm missing something basic, because there are plenty of people on here that are smarter than me.
I use the battery switch from Blue Seas posted above and the secondary charging lead. I don't use a combiner. I don't use BEP anymore since the last one fell apart. The Blue Seas product seems much stronger. I like simplicity.
I use the battery switch from Blue Seas posted above and the secondary charging lead. I don't use a combiner. I don't use BEP anymore since the last one fell apart. The Blue Seas product seems much stronger. I like simplicity.
Now I'm confused...the switch from Blue seas mentioned above IS a combiner.
Now I'm confused...the switch from Blue seas mentioned above IS a combiner.
You may have misunderstood. The switch combines the house and starting batteries for emergency start. A combiner, on the other hand, "is a voltage-sensing relay (13.3 volts) which connects two batteries together when either is receiving a charge. When the charging ceases, the relay opens so that each battery operates independently." From Yandina website. See the difference?
I have the 2nd charger wire from my E-Tecs along with a battery charger/monitor for 120 at the house or dock. The on board 120V battery charger/monitor charges each battery individually and gives status individually. The combiner won't alow you to do that. I still have the Blue Seas 1/2/emergency, just without the combiner, for emergency power if needed for starting.
I have twins, so there are two of the setups described above, starter and house battery on each side. I also have a single Blue Seas switch between sides to allow any battery or combination of batteries to start either engine.
If you look at the Blue Sea website for the "resources" pages, you will see the diagram for the battery switch above. http://bluesea.com/viewresource/681 In my case, my twins alternate charging leads go directly to my house bank, fused of course. Yours would do the same. Everything else would be as the diagram shows.
You may have misunderstood. The switch combines the house and starting batteries for emergency start. A combiner, on the other hand, "is a voltage-sensing relay (13.3 volts) which connects two batteries together when either is receiving a charge. When the charging ceases, the relay opens so that each battery operates independently." From Yandina website. See the difference?
The switch that was referenced above had this to say from the web site:
The link was in ncbeachbum's reply to what he had on his Contender
"A complete two battery bank management solution
Dual Circuit Plus™ Battery Switch isolates engine and house circuits, and combines battery banks for emergency starting
The 120 Amp SI ACR automatic charging relay combines batteries for charging"
That leads me to believe that its a combiner as well as an emergency parallel.
The link from ncbeachbum above is a combination of the ACR and battery switch. I was referencing the "dual circuit plus" battery switch only. The link I provided will show you what I mean.
I'm probably not describing this very well, so I appreciate everyone's help. Sometimes I need things explained to me more than once.
So here's what I got so far:
1) a battery combiner/acr/add a battery will bridge both batteries when the voltage is above a certain level, enabling me to charge both.
2) a 2nd charging lead would also enable me to charge both
3) If I have the engine on batt 1, and all electronics on batt 2, and I want the engine to charge both with having to fiddle with switches each time, was is the difference between a battery combiner vs using a 2nd charging wire?
Your description is fine. I think it's just a matter of preference. The combiner is another device, but then again you wouldn't need the extra charging cable and a 150 amp fuse. I set mine up without the combiner because BEP used to make a cluster without the VSR. It broke apart and they no longer make it, so I went with the same basic setup but with Blue Sea switches. Either way, you won't have to fiddle with switch settings other than when you need the emergency combine feature.
Your description is fine. I think it's just a matter of preference. The combiner is another device, but then again you wouldn't need the extra charging cable and a 150 amp fuse. I set mine up without the combiner because BEP used to make a cluster without the VSR. It broke apart and they no longer make it, so I went with the same basic setup but with Blue Sea switches. Either way, you won't have to fiddle with switch settings other than when you need the emergency combine feature.
KISS!! I see no advantage to installing the combiner if the aux charging lead acts like a combiner making sure the cranking battery voltage comes up before dumping charge into batery # 2. Though very unlikely just another thing to fail.
Just to be clear, the secondary charging lead goes straight to the house bank. The banks are completely separate unless you combine them for starting purposes. In my case, with twins and three banks, I can only combine my two starting batteries. I have one "on-off" switch for the house and the "dual circuit plus" switch for the 2 crankers. When I turn the dual circuit switch to "on", it energizes both starters separately. It only combines the 2 crankers when the switch gets turned to "combine." With another switch, I could also combine my house and cranking banks. My thought process was that although it's possible that both crankers could fail at the same time, I thought that it was more likely one would go first. I thought it more important to isolate the house and crankers.
Last edited by tg; 02-01-2010 at 02:49 PM.
Reason: clarity
battery combiner or 2nd charging wire? 
