Battery or electric system problem?

[Ted Pounds]

To quote Calder:  "(W)hen batteries are paralleled, one dead cell in one battery can pull down all the bateries, potentially killing them.  Additionally, small circulating currents between batteries increase their rate of self-discharge."  For those reasons I would not 'hard-wire' batteries in parallel.  It's OK to parallel them with a battery switch because, if a problem arises, you can un-parallel them.  Calder goes on to say: "Where large-capacity battery banks are neeeded, it is preferable to use two high-capacity 6-volt batteries in series rather than two smaller capacity 12-volt batteries in parallel."  So, Ron, I would reccomend replacing the two 12's in your house bank with 2 golf cart batteries ($45 ea at Sam's Club) keeping the same 200ah capacity.  And if your shorepower charger has only one output then you need a combiner for it.  Though I think the better option would be to get a new charger with multiple outputs.  That let's the charger tailor the charge to each bank.

Ted

[Stu Jackson]

C34 Electrical Systems

Just a couple of comments on the previous few posts.

1.  Battery combiners are wired between the battery banks, NOT "between the alternator/regulator and the battery banks."

They essentially take the place of the 1-2-B switch.  The description below is from the West Marine Advisor at:
 http://www.westmarine.com/webapp/wcs/stores/servlet/WestAdvisorDisplayView?advisor=464-465.htm

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How do I charge both banks simultaneously?
By isolating starting and house banks, you face a challenge trying to charge them from a single source like single-output chargers or alternators. If you violate the "separation" of the two banks, you face the probability of two dead batteries due to "operator brain-fade". That's why we are great believers in the West Marine Battery Combiner and Heart Pathmaker, Balmar Dual Output Alternators, and to a lesser degree, battery isolators. These products sense the voltage of the battery banks and connect the batteries together whenever one battery's voltage is elevated. Both banks charge simultaneously and remain combined until the voltage drops, whereupon they are disconnected from one another. It's much like having a very attentive engineer flip your battery parallel switch on and off at exactly the right moment. The result is maximum charging performance for two banks, and complete isolation of the two banks to ensure that you can start your engine.

Do I have to scrap my present switch?
While you don't have to, we strongly recommend the use of simple-to-understand OFF-ON switches. Shoot, even your brother-in-law can probably figure out how to operate an OFF-ON switch, but might be completely baffled by a OFF-1-BOTH-2 switch. Alternatively, you can use your current battery switch, plus a second OFF-ON switch, but we think it becomes complicated to understand what each switch combination accomplishes. As an added benefit, the fact that the battery switches are seldom, if ever, operated while underway greatly reduces the chances of damaging your alternator by accidentally opening its output circuit.

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Battery isolators take up voltage, and shouldn't have to be used since they are way old technology.  You could use the switch or a combiner FOR A SINGLE SOURCE OF CHARGING INPUT.  But remember, it's ONLY because of "brain fade" in forgetting to switch the 1-2-B switch!!!  If you can remeber to do that, you don't need a combiner or an echo charger!  Islators are crazy:  I ripped the iolators out of our boat when I first bought it.  They drop between 0.6 to 1.0 volts.  Why ever consider them?

I personally disagree with West's idea of the battery switches.  I discussed this in the earlier referenced post with Kyle Ewing.  If you can remember to switch the battery switch, why spend the money for extra switches?  However, if you're redoing everything, it's not a bad idea for simplicity or if you're "switch-challenged." (more brain fade...)  On our engine kill lever, I have a little Dymo label says; "2" - it reminds me to switch the battery switch if I start on our start battery #1.  Once the engine is off, just use the house battery.


2.  Reference to Calder's comments on paralleling batteries:  Yes, he did say that.  However, you need to take it in context because he also goes on to talk about large house banks, the complete text of which I've posted on this board at least twice. (Search on Calder, you should be able to find it.)  Sure, a cell can go bad, which is what started this thread in the first place, but even Calder's answer is just take that battery out of the system.  How can you ever build a large house bank without paralleling batteries?  Also, two 6V batteries in series could have the same problem, or more than one battery in any bank, for that matter.  The idea is to maintain your batteries with a reliable charging system.


3. "...discusses charging with a single alternator output and even two alternators but he doesn't cover much about how to add an AC charger in the circuit."  

Ron, think of it this way:  The charger and the alternator SHOULD NOT BE ON TOGETHER - ever.  You don't add it INTO the circuit between the alternator and the bank, it is a separate source.  Then the concept is simpler.  

The shorepower charger, whether multiple or single outlet, charges the batteries when you're plugged in.  The alternator charges when you're running the engine.  

I think I understand your concern which is:  "What happens when I use a multiple output shorepower charger IF I have installed a combiner to split the charge from the alternator? Won't the combiner combine when the multiple shorepower charger is on?  Will this harm the system?"  You could install a shutoff switch on the combiner for when you are using the shorepower charger, but this adds complexity and another switch, which is what you are trying the AVOID in the first place!  BTW, the combiner literature does cover this and includes the idea for the switch.

Go back to my discussion above.

You have two choices:  use only one output from the charger to the house bank, wire the alternator to the house bank, too, and use the combiner or get an Echo Charger.  The advantage of the echo charger over the combiner is that you won't overcharge your starting battery.  One of our electrical guru's was recently cruising in the Abacos and found that the combiner overcharged his start battery when motoring for enough time to replenish his house bank.  That's why the echo charger is better, since the start bank is almost always full.


4.  "Many do not motor nearly long enough to fully charge the their battery banks so most of the work is done at dock side by the AC charger. For these folks a good charger is well worth the extra expense."

That's correct.  IF you still have the original internally regulated OEM alternator and you don't have an external regulator for your alternator.  We've also discussed this in great length.  Do a find on alternators, regulators, etc.  Also, Calder explains this in detail in his book.  Automotive regulation just doesn't work for boats, which is why many of us are still so disappointed that boat manufacturers continue to produce electrical systems that are prone to immediate failure right out of the box.  Geez, two lousy small batteries, with plasma screen TVs, refrigeration, lights galore.  It boggles the mind, and makes these discussions necessary.  Welcome, but necessary.  This is a fascinating topic.

Just to summarize:  as we've said before ONLY YOU can determine how you plan to use your boat.  If you're plugged into marinas (your choice) much of this "how do I charge with my alternator?" is absolutely meaningless to you.  However, if you like to be out and away from it all for extended periods, AND you don't want to use the 1-2-B switch to manually parallel your charging from single sources like alternators and solar, then you get involved in combiners and echo chargers.  It CAN all be done manually, too, don't forget.

Last, but NOT least, IN ANY EVENT, get a darned good charger, which, in our (C34) combined experience, is the Statpower Xantrex 20 or 40, or a Trace or Heart combined inverter charger.  If you don't you'll end up spending $$ on replacing batteries.  Why not keep the batteries and get an instant return on investment with a quality three stage charger.  This applies to any kind of use of the boat.

Stu

PS  Ron, a representative wiring diagram is on the Projects page:  http://kindred-spirit.net/upgrades/wirediagram.html

It has a combined inverter charger with a combiner.  You'll not that the alternator and the charger are wired to the house bank.  If you sketch it out for your boat, it may help you figure this out.

[tandm]

Stu, my error.  I was mixing the concept of an isolator with a combiner.  An isolator sits between batteries and the regulator but, as pointed out, a combiner does not. This is one of the reasons I like this message board, bad information usually gets caught and corrected.

I do have an alternative view on larger alternators and external regulators, because no matter the alternator, you still have to run the auxiliary.  My idea of getting away from it all includes, kerosene lamp, no TV, no stereo, a good book and lots of sailing.  The stock 50A alternator, an external regulator and a Statpower Xantrex 20 (for when I get home) work just fine.  My choice.  :)

td

[Ron Bukowski]

Thanks Stu,
Your last post has cleared up a lot of questions for me. That isn't to say that I won't be back with more; for now I have it pretty straight in my mind. Al's wiring diagram is just about what I diagramed for myself previously but it helps my confidence to hear it from someone who has been down the path before me.

[Stu Jackson]

TD:  I wholeheartedly agree with you.  In fact, we still have the OEM alternator!  Would you believe that?  We also have an old AutoMac regulator.  That gives me external manual control over the alternator, so I can get a little more out of it than with just the internal regulator.  So, because of the way we use our boat, and my energy budget and house battery bank of 315 AH, I know how far I can go.  We've been out for four days without having to recharge, with our chosen necessities all operable.  I just plug in to shorepower a day before we leave on any extended cruise.  We do not keep the boat plugged in all the time, using an 11 watt solar panel to offset the self discharge of the wet cells.  Rushing to put in a higher output alternator is not necessarily a requirement, but is, as you say, a choice, and based on how you use your boat.  In the near future I plan to replace the old alternator (it has been going for over 18 years!) with a 75 to 90 [no bigger] with external regulation.  I just reinstalled my kerosene lantern (next week we'll switch to lamp oil since the wick needs to be replaced), and we're very careful about energy.  I haven't installed my (four year old) Link 2000 (yet) because I can tell you at any given time what the amp hours are from my budget and doing the math in my head (not the wc!).  KISS is a great idea.  Am I guessing that when you said "The stock 50A alternator, an external regulator and a Statpower Xantrex 20..." you meant INTERNAL regulator with the stock alternator?

Ron:  Please keep asking, that's what we're here for, and hope we're not confusing things too much by giving you all the options.  Just like life, there isn't only ONE right way to do it.  Aren't choices great?

Stu

PS  just a reminder if you haven't seen it already in previous posts, take a look at www.amplepower.com for the Ample Power Primer.  Very good info on batteries and charging.

[This message was edited by Stu Jackson #224 1986 "Aquavite" on November 30, 2003 at 12:17 PM.]

[Ray & Sandy Erps]

TD and Stu,
Could you expand a little bit more on your stock alternators with external regulators?  I did a little checking yesterday and found the amplepower web site.  It was very informative, but after looking at their price list, I figured I could ruin batteries for 30 years or more before it would pay for itself.  We have a fridge, but it's not on unless we're motoring and the beer isn't cold yet.  Other than that, our power use is pretty low, as we've been accustom to smaller boats with a single house battery for years.  

I'm interested in getting more out of my stock alternator though, if the price is right.

[Stu Jackson]

Alternators

Ray

It is rare for people to change their stock alternators to externally regulated.  Part of the reason is that external regulators will "work" the alternator much harder, especially if the battery bank is low, which is, of course, when you need the power the most.  The OEM alternators are not as good running full bore, or hot, as are the newer replacement alternators.  I believe Ample discusses this on their website.  It's not in the Primer, but should be under the section on regulators in manuals or equipment.

You will NOT be able to get anything more out of your stock alternator as currently wired and regulated.

Re the cost of replacement alternators, you may want to check out www.jackrabbitmarine.com. They sell Ample alternators for less than Ample does, I think.

In one of my earlier posts on alternators, I asked if the original OEM 55 A Motorolas could be rewired to have external regulation (see references below).  The reason I asked was because I was helping a friend who had an external regulator, but hadn't bought a new alternator and he was interested in trying that.  The answer was yes, but because of the issues discussed above we decided not to do that.  He eventually bought a Balmar 912-75 and we installed it and the regulator together.  He did have to shave down the bracket to get the fan blades on the Balmar to fit.  The Ample alternators do not have the fan blades on the forward face, they look just like the old Motorolas, so the bracket does not need to be shaved.

Having not heard back from TD, I still am assuming he did mean internal, not external regulation on his OEM alternator from my post yesterday.

It's not so much about ruining batteries, but simply giving them a charge when you need it when you are not plugged into shorepower.  The OEMs with internal regulation just won't give you a decent charge even if you run them for hours.  By decent, I mean full, and three stage (efficient, and good for the batteries).

Just check the voltage output at the batteries, they're simply like tapering chargers, which don't provide the correct three stage charge.  They're under voltage (13.8 if you're lucky), and very low on amperage once the batteries start to accept the charge.  That's why we refer to them as automotive.  I think that concept was covered by Ample, and West Marine's Advisors also give a reasonably good description.  The best description is in Calder's Boatowner's Manual.

Again, though, with a low load as you describe, and the way you use your boat, unless you depend on your alternator to provide you with charging, you can live with it.  It's not ruining your batteries, but isn't doing them much good either because they're not being charged properly when you're running your engine.  It would ruin your batteries eventually if the ONLY source of input was your alternator.

But if they're being charged properly by a three stage shorepower charger, then they're in good shape and don't need much, if anything from the OEM alternator, so it's not putting out much because it doesn't have to when you run your engine.

Keeping your loads to a minimum certainly helps.  Do a FIND on "batteries and the fridge."  Seems like you and I use our fridges in the same way, while some folks keep them on all the time.

Stu

Some earlier references:

http://c34.infopop.cc/6/ubb.x?a=tpc&s=329609511&f=829605811&m=238600304&r=171603304#171603304

http://c34.infopop.cc/6/ubb.x?a=tpc&s=329609511&f=829605811&m=854606703

http://c34.infopop.cc/6/ubb.x?a=tpc&s=329609511&f=829605811&m=671604581

The post about the external regulation on the OEM Motorola is:

http://c34.infopop.cc/6/ubb.x?a=tpc&s=329609511&f=829605811&m=933602911

[This message was edited by Stu Jackson #224 1986 "Aquavite" on December 01, 2003 at 12:07 PM.]

[tandm]

Thanx to the previous owner we have a stock alternator and an external Ample "Deep Cycle" 3 stage regulator.  This was duly noted in the boat's prepurchase survey.  Based on the PO's notes and logs, the regulator was installed in February of 1992. I eye the whole setup wearily every time I am "under the hood" but so far so good.  It will be time to go to a 75a high output alternator, etc. at some point in the not to distant future; not because we need the extra capacity but because the current alternator is getting very long in the tooth. But first a new 150 jib...

td

[Stu Jackson]

TD

I should have remmbered from the earlier posts that you had had the external regulator installed on your OEM.

Glad to hear it is working.  What's your house bank capacity?

Stu

[tsoko]

TD,
When you decide to upgrade alternators, you really should consider the setup that Rodd Collins describes in the C36 website.  I followed his advice and purchased a LeeceNeville 90A alternator this past spring for about $225, and it was a direct replacement.  No shaving brackets, no changing belts, no worries.  The "smart" regulator I installed back in 92? 93? works wonderfully with it.  It's great to see a steady 70-80 amps going into the house bank at cruising RPM's.  Just my humble opinion.

[Ray & Sandy Erps]

Tom,

Did you have your smart regulator hooked up to the original alternator before you bought the new LeeceNeville?

Do the new hi-output alternators act like an automotive alternator without a smart regulator, or do they come with a fancy-smancy regulator?

[tsoko]

Ray,
Yes, I did have the smart regulator hooked up to the original alternator for the past 9-10 years.  It worked fine, but under optimum conditions it would only put out 40-45 amps.  Rodd Collins article tells that the LeeceNeville come with a standard automotive regulator.  You have to ask for an external regulation plate.  From there it is easy to hook up your favorite smart regulator.  Here's the link to the article:
http://www.catalina36.org/Article_alternator-battery.htm

[Stu Jackson]

C36

Tom

Thanks so much for the reference to Rodd's great writeup.

We've always been proponents of the fact that our C34s and C36s have the same systems, and appreciate any and all "cross fertilization."

Thanks again,

Stu

PS

Ray

All the new alternators are externally regulated.  You need to get a separate regulator, including the referenced C36 arrangement.

Please note that this an OLD thread, but the CONCEPTS are still valid.  Stu --- July 2010