Battery Charging

Jul 14, 2015
840
Catalina 30 Stillhouse Hollow Marina
If I have the batteries hooked up the normal way to be able to switch between 1 and 2 or ALL. When I hook up charger to 1 will they both charge?
 
Nov 7, 2012
678
1978 Catalina 30 Wilbur-by-the-Sea
If you set the switch to "ALL" yes. On our switch we also have an Off that disconnects everything. Nice when working in the DC fuse panel. I have our solar panel hooked to the distribution side of the switch, it allows us select which battery bank is charging, we usually leave is set to "ALL".
 
Jul 14, 2015
840
Catalina 30 Stillhouse Hollow Marina
If you set the switch to "ALL" yes. On our switch we also have an Off that disconnects everything. Nice when working in the DC fuse panel. I have our solar panel hooked to the distribution side of the switch, it allows us select which battery bank is charging, we usually leave is set to "ALL".
Mine is the same, but should I hook to battery or switch?
 
Nov 7, 2012
678
1978 Catalina 30 Wilbur-by-the-Sea
My solar panel is at the switch. If you have a lower cost single battery charger I would probably put it at the switch also.

I also have a 3 bank marine charger that hooks directly to the cells. It came with instructions on where to hook it up as the charge controller in it checks the individual battery condition before starting to charge (looks for short etc.). If you have a higher grade battery tender you may need to read the instructions. We never use our charger it as the solar does the job without the $25 a month shore power fee.
 
Sep 23, 2009
1,475
O'Day 34-At Last Rock Hall, Md
Our boat has the ac and solar chargers wired directly to the batteries. So both batteries are charged together by solar and ac. The selector switch controls which battery is feeding the dc distribution panel and receiving the alternator output. There may be other ways but the setup has worked well. Just make sure that the batteries are fused properly as Maine Sail has detailed on his blog.
 
May 24, 2004
7,164
CC 30 South Florida
Only if you set the switch to "All". Regarding how to use the switch it would depend on whether you have a separate starter battery or not. We just have two deep discharge batteries to perform dual function for starting the engine as well as a house batteries to service the loads. We have them hooked up through a 1,2,Both, Off switch. When underway we usually engage just one battery to keep the other in reserve for starting the engine by preventing an accidental discharge to both batteries. We also alternate the use of battery #1 and battery #2 in successive outings. This is done to exercise both batteries and to approximately maintain an even number of charge/discharge cycles. We may engage "Both" when we are motoring and wish for both to receive charge from the alternator. I'm very diligent about checking the battery switch frequently making sure it is not to "Both" when I do not desire it to be. There would be advantages to combine battery #1 and #2 but I just feel that having a backup supersedes them. The use of a generator or solar can add different choices but neither will give you a fast charge to start the engine. We have a generator to drive our twin leads battery charger and usually take a 12V power pack on trips but still try to maintain one battery in reserve. We also use wet cell batteries as replacements can be found anywhere and they candle a fair amount of abuse.
 
Feb 26, 2004
23,003
Catalina 34 224 Maple Bay, BC, Canada
WADR to the nice folks who answered your question, NO ONE KNOWS unless you provide a wiring diagram of how YOUR boat is wired.

Think about it. Your PO or YOU may have done something to the wiring that may be different from OEM factory, either a mistake or an improvement.

What you need to be doing is to trace your wiring and make up your own wiring diagram and then learn HOW and WHY it works, yourself.

Here are some ideas:

OEM 1-2-B Switch Wiring History http://c34.org/bbs/index.php/topic,4949.msg30101.html#msg30101

Basic Battery Wiring Diagrams This is a very good basic primer for boat system wiring: http://c34.org/bbs/index.php/topic,6604.0.html

This is another very good basic primer for boat system wiring: The 1-2-B Switch by Maine Sail (brings together a lot of what this subject is all about)
http://forums.catalina.sailboatowners.com/showthread.php?t=137615

They come from here: Electrical Systems 101 http://c34.org/bbs/index.php/topic,5977.0.html
 
Jun 2, 2014
596
Catalina 30 mkII - 1987 Alamitos Bay Marina, LB, CA
@JohnVTX, do what Stu says... :) Read the info and figure out what you have first.
I re-wired my boat to one of the non-factory recommended ways described in some of the info Stu gave you and now I don't worry about anything anymore (well, not anything, just not my battery charging).
Here's a basic diagram of pretty much what I have now. So, MY switch doesn't matter what position it's in anymore. It's always charging both batteries by the engine or AC charger, and I now use position 1 as the "main" battery and only switch to #2 (reserve) if I drained the first one by accident. I also upgraded my battery wiring to 1/0 size and engine starting is very happy.

battery_wiring_diag.jpg
 
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Feb 26, 2004
23,003
Catalina 34 224 Maple Bay, BC, Canada
jon,

That is a SUPERB wiring diagram. It makes the main basic connections very easy to read. Would you mind if I "pirated" it and included it in my oft-linked battery wiring diagram thread on our C34 website? Of course, I'd use proper attributions. Would you send me the original jpg so I can post it there?

Thanks,

Stu


@JohnVTX, do what Stu says... :) Read the info and figure out what you have first.
I re-wired my boat to one of the non-factory recommended ways described in some of the info Stu gave you and now I don't worry about anything anymore (well, not anything, just not my battery charging).
Here's a basic diagram of pretty much what I have now. So, MY switch doesn't matter what position it's in anymore. It's always charging both batteries by the engine or AC charger, and I now use position 1 as the "main" battery and only switch to #2 (reserve) if I drained the first one by accident. I also upgraded my battery wiring to 1/0 size and engine starting is very happy.

 
Jun 2, 2014
596
Catalina 30 mkII - 1987 Alamitos Bay Marina, LB, CA
jon,

That is a SUPERB wiring diagram. It makes the main basic connections very easy to read. Would you mind if I "pirated" it and included it in my oft-linked battery wiring diagram thread on our C34 website? Of course, I'd use proper attributions. Would you send me the original jpg so I can post it there?

Thanks,

Stu
Stu, no need for any credit. If you like it, take it! PM sent too.
 
Jan 30, 2012
1,140
Nor'Sea 27 "Kiwanda" Portland/ Anacortes
Excellent diagram to be sure. Maybe re-label the 'Batt Comb' box because someone thought it was supposed to be a manual combining switch.

Charles
 
Last edited:
Feb 26, 2004
23,003
Catalina 34 224 Maple Bay, BC, Canada

mortyd

.
Dec 11, 2004
952
Catalina 30 easy living
guys. slow down. among other things catalina itself changed the wiring. by the time my boat was made in '91 the master switch kept the batteries live even when the switch was turned to 'off'. it is clealy so placarded.
 
Jun 2, 2014
596
Catalina 30 mkII - 1987 Alamitos Bay Marina, LB, CA
guys. slow down. among other things catalina itself changed the wiring. by the time my boat was made in '91 the master switch kept the batteries live even when the switch was turned to 'off'. it is clealy so placarded.
That sounds weird.
 

mortyd

.
Dec 11, 2004
952
Catalina 30 easy living
it is wired that way so the bilge pump will work even with the batteries switched to 'off.' what's wierd about that?
 
Jun 2, 2014
596
Catalina 30 mkII - 1987 Alamitos Bay Marina, LB, CA
Mortyrd, that's not what we're talking about. Everybody's bilge pump wiring should be like that. That is normal. We are talking about how the 1-All-2-Off switch affects battery charging, how most boats are wired by default, the shortcomings of that design and the ideal way to fix it.
The default wiring leaves risk for batteries to be mis charged, alternator diodes blown, and a handful of other things.