Reply
 
Thread Tools Display Modes
 
Old 04-03-2016, 07:30 PM   #1
Guru
 
City: Hampton, va
Country: USA
Vessel Name: Didi Mau
Vessel Model: 2003 Ocean Alexander 456
Join Date: Jul 2015
Posts: 610
Battery management

The current situation:

I Close tomorrow on my (new to me) 2003 Ocean Alexander 456. I need new batteries. All of them are bad. It has 2 8d gel cell batteries for the house bank, one each 8D lead acid battery for each engine, a 4D battery for the 12 KW generator and a Group 31 for the 6KW generator. All batteries but the house bank are normal lead acid and the house bank is gel. The engines each have a 115 amp alternator. The alternator, I believe, is regulated for a lead acid batteries.

I am having batteries delivered to the boat on Tuesday and need to tell the shop on Monday what type of batteries to bring. I hope to take the boat from Pompano Beach Florida on Friday to Norfolk Virginia.

My thought is to continue with the current configuration of the gels for the house bank and lead acid batteries for everything else. The house bank has his own charger which is programmable for jail cells. The 12 KW generator and two engine batteries are all tied to A 30 amp charger. The 6KW generator is tied to a trickle charger.



My thought is that I can parallel the engine batteries in the house bank while the engines are running, which will provide a total of 230 A of power to the 4HD batteries. Gels take a higher voltage the lead acid and should not be harmed by the lower charge voltage put out by the engine alternators. I will top the batteries off periodically wall I sure power or while running the generators. I understand that when running the charger I will have to open, that is to say, shut off the parallel connection between the house bank and the engine batteries.

Does this configuration and my plan for battery power management makes sense to those of you who were experience with trawlers?

Gordon
__________________
Advertisement

Gordon J is offline   Reply With Quote
Old 04-03-2016, 07:34 PM   #2
Guru
 
caltexflanc's Avatar
 
City: North Carolina for now
Country: USA
Vessel Name: Small Incentive
Vessel Model: Boston Whaler 130 Sport
Join Date: Aug 2011
Posts: 3,802
Personally I would rather have AGMs than gels, or plain old deep cycle lead acid flood batteries for house use and simplicity.
Who are you using for a supplier down there? I've done most of my heavy battery buying in So. FL.
__________________

__________________
George

"There's the Right Way, the Wrong Way, and what some guy says he's gotten away with"
caltexflanc is online now   Reply With Quote
Old 04-03-2016, 07:43 PM   #3
Guru
 
City: Hampton, va
Country: USA
Vessel Name: Didi Mau
Vessel Model: 2003 Ocean Alexander 456
Join Date: Jul 2015
Posts: 610
George, I am having the batteries delivered by Fort Lauderdale battery. They are charging 500 for gels and $550 for AGM. That is for 8Ds. I would use all lead acid, but the house bank is in a very difficult spot and it is difficult to monitor the electrolyte. I would essentially have to take the cushion off a Settee, open the floor and crawl into the into the ER to check the electrolytes. That is a lot of work to go through and no maintenance batteries would be so much easier. I was thinking of jel cells for the house bank, because their charge voltages more closely resemble normal lead acid batteries. When using the two engines to charge all the 8D batteries I thought that the greater similarity between gels and lead acid Would result in a happier charging system.

Girdon
Gordon J is offline   Reply With Quote
Old 04-04-2016, 07:29 AM   #4
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 16,531
"I would essentially have to take the cushion off a Settee, open the floor and crawl into the into the ER to check the electrolytes."

Perhaps not needing to check weekly would be a help?

Hydrocap | Information

www.hydrocapcorp.com/info.htm


HYDROCAPS are a must for lead-acid battery users. Just look at the increased safety, reduced maintenance, increased battery longevity and reliability as well ...
FF is online now   Reply With Quote
Old 04-04-2016, 07:36 AM   #5
Guru
 
ranger42c's Avatar
 
City: Maryland
Country: USA
Vessel Model: 42' Sportfish
Join Date: Aug 2013
Posts: 3,159
Quote:
Originally Posted by Gordon J View Post
Gels take a higher voltage the lead acid and should not be harmed by the lower charge voltage put out by the engine alternators.

I'm almost positive I've seen battery specs where gel charging voltages are LESS than FLAs. You might double-check, using manufacturer's specs for all your specific target batteries.

I could be wrong, of course. Memory would perhaps be a wonderful thing... if I had one.

I think I'd investigate 6V golf cart batteries for the house instead of the 8Ds. Two 8Ds is about 490 Ah. Six GCs is about 660 Ah, and might fit in approx. the same physical space. Lifeline (and maybe others) makes AGM 6Vs, so no maintenance. And each individual batteries weighs less than an 8D, so you might survive the schlepping a bit better.


Whatever... you'll want your charger(s) to be right for the optimum regime each bank as suggested by the battery manufacturer, no matter what chemistry or configuration.

-Chris
__________________
South River, Chesapeake Bay
ranger42c is offline   Reply With Quote
Old 04-04-2016, 08:29 AM   #6
Guru
 
City: Hampton, va
Country: USA
Vessel Name: Didi Mau
Vessel Model: 2003 Ocean Alexander 456
Join Date: Jul 2015
Posts: 610
I appreciate the comment about golf cart batteries. Perhaps next time that I change out batteries. I really don't want to go through the work now love making cables and reconfiguring a boat. My cast now is to take the new boat 1000 miles of the ICW and park it in my backyard.

I think my question might be boiled down to the following: Will running both engines and keeping the engines 8D batteries parallel with the two HD house batteries charge all four batteries with 230 amp hours, but can find out put a boat engine alternators? Will each of the alternators see the other and monitor their output accordingly?

Thanks and advance for your thoughtful answers.
Gordon J is offline   Reply With Quote
Old 04-04-2016, 09:05 AM   #7
Dauntless Award
 
Wxx3's Avatar
 
City: New York, NY
Country: USA
Vessel Name: Dauntless
Vessel Model: Kadey Krogen 42 - 148
Join Date: Jan 2013
Posts: 2,313
No.
Why spend a lot of money becuase you are in a hurry?
If you take the time to have along term plan, there is no reason why whatever batteries you choose can not last 5 to 8 years, maybe more.

However, by having a variety of batteries, with all different chemistry, you are cruising for a bruising.

Your current plan leaves you no secondary charging backups with changing or screwing up something.

Personally, I would go with all AGM's or Golf Cart, with the only exceptions being the start batteries for Engines and Gen.

Also, in my research, I have seen NO advantage of GEL over AGM and some disadvantages, which I frankly don't remember because at that point, I'd made up my mind.

Also, chronic under charging a battery will lead you being in the same situation a year or two from now.

Please Gordon. Take a deep breath and slow down, if only ONE day.
__________________
M/Y Dauntless, New York
a Kadey Krogen 42 Currently https://share.delorme.com/dauntless
Blog: https://dauntlessatsea.com
Find us: https://share.delorme.com/dauntless
Wxx3 is offline   Reply With Quote
Old 04-04-2016, 09:56 AM   #8
Guru
 
djmarchand's Avatar
 
City: East Greenwich, RI
Country: USA
Vessel Name: Bella
Vessel Model: Mainship Pilot 34
Join Date: Aug 2012
Posts: 2,882
Gel Cell batteries were first developed for aircraft and other applications where venting, tipping and inversion were problems. AGMs then came along and are superior in all respects to Gel Cells. So if you have to use 8Ds and don't want to have to check and add water, then use AGMs and not Gel Cells. Flooded cell batteries would be cheaper, but unless you go with very expensive batteries, true deep cycle batteries are generally not available in 8D sizes. Any battery charger with a Gel Cell setting probably also has an AGM setting, so make that switch. The AGMs should work fine if paralleled with your alternator output as they have a similar charging profile to flooded cell batteries.


But I absolutely hate 8D batteries. All it takes is a single jumper wire to make two GC batteries work in place of an 8D, so it is not a big deal to switch.


But what kind of boat are these in? The Beneteau 423 listed in your profile doesn't have two engines and would not need an 8D to start it if it did, so it must be something else. What engines do you have? 8D starting batteries are almost certainly overkill unless they are DD 6-71s or similar "big iron".


And finally, you have 115 amp alternators on these engines. Are they externally regulated with a three stage charger. If not, you will not see anywhere near a 230 amp charging rate.


DC battery management is one of the most complex things to think about, configure properly and operate properly on a long term cruising boat. It is almost impossible to understand your system and your DC needs and offer a comprehensive solution over the internet. You probably need to spend some time with a qualified marine electrician.


David
djmarchand is online now   Reply With Quote
Old 04-04-2016, 09:56 AM   #9
Guru
 
City: Hampton, va
Country: USA
Vessel Name: Didi Mau
Vessel Model: 2003 Ocean Alexander 456
Join Date: Jul 2015
Posts: 610
I am no fan of gels. Mixing AGMs and normal lead acid CAN be detrimental to AGMs, but not necessarily so. And I will probably go with AGMs. My question had more to do with using both engine alternators simultaneously to charge start batteries and house bank.

My sail boat had only one engine and. House bank of 4 rad AGMs batteries. The start battery was also AGM. I never used the start battery but instead used the house bank exclusively. So, I was charging the house bank when motoring.

Now, is the logic the same when running two trawlers? If both engines are running in parallel with house bank, do I have a potential charging output to house bank of 200 plus amps? OR, will the two alternators see each other and reduce their output?

This boat also has two gensets that have separate start batteries, so theoretically, I should never be in a bind electrically, if I forgot to open the parallel switches and ran the engine starts two low. (And of course I know that is not good for the batteries).

So let's assume that I have thoroughly researched batter chemistry, understand the potential improvemen of golf cart over 12 volt.

Thanks again for your answers and input.
Gordon J is offline   Reply With Quote
Old 04-04-2016, 10:05 AM   #10
Guru
 
City: Hampton, va
Country: USA
Vessel Name: Didi Mau
Vessel Model: 2003 Ocean Alexander 456
Join Date: Jul 2015
Posts: 610
David,

Answers to some of your questions I original post. Engines are Cummins 6BTA5.9

The problem of golf carts is two fold at my current location: battery box configuration and making battery cables.

Understand that I may not get the total of both alternators; my question had to do with two alternators charging house bank and start batteries...what issues might I face. With charging voltages of 13.8 - 14.2, the AGMs will never be topped off until I turn on generators or connect to shore power.

So my question has more to do with using engine alternators to charge house AGM bank.

Gordon
Gordon J is offline   Reply With Quote
Old 04-04-2016, 10:11 AM   #11
Guru
 
ranger42c's Avatar
 
City: Maryland
Country: USA
Vessel Model: 42' Sportfish
Join Date: Aug 2013
Posts: 3,159
Quote:
Originally Posted by Gordon J View Post
Mixing AGMs and normal lead acid CAN be detrimental to AGMs, but not necessarily so. And I will probably go with AGMs.
Can't speak to the alternator question...

When we started our switch-over from FLA to AGMs, I asked the Odyssey guys about mixing... 'cause I had one dying bank of 3x Group 31s, one good banks of 3x G31x, and one good genset starter battery (G27, I think)... all on the same charger. And there's that pesky expense thing; didn't want to buy it all at once, if I could help it.)

The charging profiles for the FLAs and the AGMs were similar, but not identical. The charger has a switch only for FLAs or Gels. The charger guys (and their manual) said use the FLA setting for AGMs.

The Odyssey guy told me the charging profiles were close enough so we could replace the bad bank, keep using the good bank and the good genset battery, and all on the same charger.

(Then we eventually replaced the other banks, about 3-1/2 years later.)

That first bank of AGMs has been through 10 seasons, now, still holds voltage somewhere up near full. (And the others still act like new.)

As I said before, Lifeline makes 6V AGMs, so you can (if you want) get the best of both golf cart and maintenance-free in the same product. Maybe others make that combo too. I haven't priced, maybe cost and arm and a leg, but it'd probably last a decent while.

I also haven't checked charging profiles to see whether such a bank could co-exist on my current charger when I have to replace the older 3xG31 bank. I'm thinking of putting an inverter-charger all alone on that bank anyway, though, if I replace 3xG31s with 4xGCs.


I think 6x GCs fit in approx. the same space as 2x 8Ds.

-Chris
__________________
South River, Chesapeake Bay
ranger42c is offline   Reply With Quote
Old 04-04-2016, 10:29 AM   #12
Guru
 
City: Carefree, Arizona
Country: usa
Vessel Name: sunchaser V
Vessel Model: DeFever 48
Join Date: Apr 2008
Posts: 6,372
Gordon

You started this thread by saying your batteries are bad. Do you know why? Until you know and can properly monitor things (BMKs, hydrometer) all advice is just guessing.

To keep it simple and get on the road, AGMs for under couch and coin flip the rest. Just don't try anchoring out though, you may be stranded.
sunchaser is offline   Reply With Quote
Old 04-04-2016, 10:30 AM   #13
Guru
 
dhays's Avatar
 
City: Gig Harbor
Country: United States
Vessel Name: Kinship
Vessel Model: North Pacific 43
Join Date: May 2015
Posts: 5,093
Gordon, I have no experience as you asked for in your initial post, but if the alternators are internally regulated I would be fearful that you won't get anywhere near the amount of charging you need and it is just a guess as to how each will respond to the presence of the other in the charging circuit.

I understand the problems of location and time that you are facing. I also recognize that you are wanting to get your question answered.

For this coming trip, a quick and dirty solution would be to keep the engines charging their own batteries and simply run your large generator to keep your house batteries charged as needed. If I understand the situation, your larger generator should be capable of your house. It is hard for us sailors to reconcile running a generator a lot, but it is what it is. When you get home, you will then have the time to come up with a final plan.
__________________
Regards,

Dave
SPOT page
dhays is offline   Reply With Quote
Old 04-04-2016, 12:44 PM   #14
Guru
 
City: gulf coast
Country: pinellas
Join Date: Jun 2014
Posts: 2,199
A group 31 will be fine for the 12KW genny.
bayview is offline   Reply With Quote
Old 04-04-2016, 12:51 PM   #15
Guru
 
City: gulf coast
Country: pinellas
Join Date: Jun 2014
Posts: 2,199
Quote:
I think my question might be boiled down to the following: Will running both engines and keeping the engines 8D batteries parallel with the two HD house batteries charge all four batteries with 230 amp hours, but can find out put a boat engine alternators? Will each of the alternators see the other and monitor their output accordingly?

Alternators only put out max current for a brief period until battery voltage increases a little. They would probably overheat if otherwise.


I sure would try to resurrect those old batts for the trip. You have enough gennu power to charge the start batteries for a start unless they are dead short. Use the genny for house lights if you are not at a dock. Get home then figure it out.
bayview is offline   Reply With Quote
Old 04-04-2016, 01:16 PM   #16
TF Site Team
 
Baker's Avatar
 
City: League City, Tx
Country: Texas
Vessel Model: Carver 356
Join Date: Oct 2007
Posts: 5,633
Quote:
Originally Posted by bayview View Post
Alternators only put out max current for a brief period until battery voltage increases a little. They would probably overheat if otherwise.


I sure would try to resurrect those old batts for the trip. You have enough gennu power to charge the start batteries for a start unless they are dead short. Use the genny for house lights if you are not at a dock. Get home then figure it out.
That was kinda my thinking. You have a ton of electrical power. Get home and then do it right. I wouldn't rush to replenish a potentially flawed system...or one that is less than optimum. Get home....sort it out...and then do it right!!!
__________________
Prairie 29...Perkins 4236...Sold
Mainship Pilot 30...Yanmar 4LHA-STP...Sold
Carver 356...T-Cummins 330B
Baker is offline   Reply With Quote
Old 04-04-2016, 01:25 PM   #17
Guru
 
City: Hampton, va
Country: USA
Vessel Name: Didi Mau
Vessel Model: 2003 Ocean Alexander 456
Join Date: Jul 2015
Posts: 610
I appreciate everybody's comments. The batteries are totally toast. I can only start the engines when I parallel all batteries and keep the battery charger on.

I believe dad to the previous owners maintenance personnel kept the batteries on parallel and charged the gels and FLA's at 14.6 V. They have been cooked. There is no question that I will be getting new batteries tomorrow. I am going down to the ER now to measure the battery boxes to see if they will accommodate golf carts.

Thanks for all the advice. I will figure out how well the alternator batteries keep the house bank afloat. I wish this boat had a status of charge meter, unfortunately it does not. That is now on my to do list.
Gordon J is offline   Reply With Quote
Old 04-04-2016, 02:23 PM   #18
TF Site Team
 
FlyWright's Avatar
 
City: California Delta and SF Bay
Country: Sacramento, CA, USA (boat in Vallejo)
Vessel Name: FlyWright
Vessel Model: Marshall Californian 34 LRC
Join Date: Apr 2008
Posts: 10,184
If you have a voltmeter, you can determine your battery charging. Select the start battery and check resting voltage. Select house batt and Check resting house V. Reselect start batt and start one engine and check V. Start second engine and check V, then stop first engine. Check V.

Select house batt and check V with second engine running. Start first engine and check V. Stop second engine and check V.

If your batt V changes each time you change charging sources, you have an indication of what's connected. If no change in V, there's no connection.

All boats can be different. Mine has been modified to always provide the charge to the respective battery regardless of switch position. The switch only selects load, not charges. The alternator charges are wired directly to their respective bank.
__________________
Al

Custom Google Trawler Forum Search
FlyWright is online now   Reply With Quote
Old 04-04-2016, 02:33 PM   #19
Dauntless Award
 
Wxx3's Avatar
 
City: New York, NY
Country: USA
Vessel Name: Dauntless
Vessel Model: Kadey Krogen 42 - 148
Join Date: Jan 2013
Posts: 2,313
Quote:
Originally Posted by bayview View Post
Alternators only put out max current for a brief period until battery voltage increases a little. They would probably overheat if otherwise.


I sure would try to resurrect those old batts for the trip. You have enough gennu power to charge the start batteries for a start unless they are dead short. Use the genny for house lights if you are not at a dock. Get home then figure it out.
Not true. A car alternator yes; but not a true marine alternator.

How do you think I charge my 880 amp/hrs every day.
__________________
M/Y Dauntless, New York
a Kadey Krogen 42 Currently https://share.delorme.com/dauntless
Blog: https://dauntlessatsea.com
Find us: https://share.delorme.com/dauntless
Wxx3 is offline   Reply With Quote
Old 04-04-2016, 02:55 PM   #20
Guru
 
djmarchand's Avatar
 
City: East Greenwich, RI
Country: USA
Vessel Name: Bella
Vessel Model: Mainship Pilot 34
Join Date: Aug 2012
Posts: 2,882
An 8D battery box will accommodate two GC batteries, but they will slide around a bit. Better to get a box that fits or put a space inside to secure them, but for short term, ok.


Two internally regulated (or three stage externally regulated for that matter) alternators will coexist fine in parallel. They will just share the load. An externally regulated alternator will recharge several times faster because the fixed voltage of the internally regulated alternator isn't enough for rapid charging past about 75% charged. A three stage regulator will push the voltage to 14.5 or so at that point, whereas the internal regulator is fixed at about 13.5 v.


8D starting batteries is overkill for everything. A good Group 31 with decent sized cables and good connections will easily start a Cummins B. Look for a Group 31 with a 950+ CCA rating. They weigh about half of what an 8D weighs. Again one will fit in an 8D battery box, but better to get one specifically made for it.


David
__________________

djmarchand is online now   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 01:39 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012