House Battery Bank for everything??

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SteveandZoila

SteveandZoila

Senior Member
Joined
Jan 12, 2014
Messages
150
Location
USA
Vessel Name
Miss Rita
Vessel Make
2004 Heritage East
OK, I am going to open a can of worms!! I have a 44' Gulfstar trawler, refitting, I am a newbie to big boats , but learning. The existing situation: I am forced to trace all wires to get this boat going, and I got to question some of the set ups. The existing batteries were 2 4D starting Batts for Perkins 6.354s, Battery for Windlass, Approx 14' from House Bank. Battery for Gen set, 8 interstate 6 volt for house bank.
Soooo! How about just one laaarge house bank of 12-14 6 volt batterys to run everything. I have room for 18 batteries, but may need less with the next generation, since I am presently planning on 50% discharge.
  • Get rid for The 4 Perko Switches
  • Understand the wiring on this boat.
  • Simple I know the diference in design of starting vs deep cycle, but would it really be th charging, same type of batteries
  • 1200-1400 amp hrs should crank anything, yes I know there is a difference in deep cycle vs starting.
  • New inverter/charger has to deal with one “battery”
  • Easier to work out larger Alternator plan and Solar.
  • With all the electronic monitoring, plus Solar panels, how could I get stranded? Also I could keep a starting battery with jumper cables for emergency. For got the dinghy!!
I know the difference in design of starting vs deep cycle, but would it really be problem with that big of a bank?
 
Interesting thought. But main reason for separation is if something in the 'house' shorts or something, and drains the batteries, you still have the start batteries to crank the engines - not so if one large bank that is dead:angel::angel:
 
I am going to enjoy reading this thread because when it comes to electricity I'm a pretty good plumber. Steve are you talking about having an inverter or just a 12 vdc boat?
 
When I did mine, I pulled out all the wiring between the master switch and batteries, there was a lot. I now have a 1080 amp AGM bank for everything and one GP31 for my generator. I've never been below 75% before recharging. We anchor out 90% of the time.
 
My opinion only.
I have used G.C batteries to start my single engine, a Cummins 555, which needs a lot of current, more than your engines. I now use all Gels.

They will work for that purpose although they do not like the high burst of power needed but over the whole bank you should be fine.
Your particular engines will require less power from them so as long as the bank is big enough , you are carefull to ensure adequate reserve to start the engines then you should be ok.

I do maintain separate engine start batteries BUT I have no Gen, and we used to winter boat in freezing weather so I either started or was stranded.

If you have a Gen. that will help so even if you flatten them too much you can start the gen as long as you ensure the gen has an isolated good start battery which is much smaller.
A lot will depend upon how you interconnect the 12 comb. how well they live with the number of batteries and connections you will have to use. Read the following site:
SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

Bank of this size require carefull set up or the minute ,to us, voltage differences, Vdrops , will add up to less than ideal performance.

You might also seriously consider talking to solar guys involved in house hold setups as they will encounter the problems with interconnections and proper wiring setups.

It would still be a good idea to maintain a separate start battery just in case.
 
Inverter

I have one vice, I have std .refrigerator, I like my cold diet cokes! and lots of food. So I and stuck with 120 volt need. Installing new Xantrx 2500 invert today. But I am changing everything to 12 volts. I look for devices that have 12 volt transformers with the ideal of have 12 volts ports around the boat rather than wall warts.
 
Thanks, I will read up .

C lectric said:
My opinion only.
I have used G.C batteries to start my single engine, a Cummins 555, which needs a lot of current, more than your engines. I now use all Gels.

They will work for that purpose although they do not like the high burst of power needed but over the whole bank you should be fine.
Your particular engines will require less power from them so as long as the bank is big enough , you are carefull to ensure adequate reserve to start the engines then you should be ok.

I do maintain separate engine start batteries BUT I have no Gen, and we used to winter boat in freezing weather so I either started or was stranded.

If you have a Gen. that will help so even if you flatten them too much you can start the gen as long as you ensure the gen has an isolated good start battery which is much smaller.

A lot will depend upon how you interconnect the 12 comb. how well they live with the number of batteries and connections you will have to use. Read the following site:
SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

Bank of this size require carefull set up or the minute ,to us, voltage differences, Vdrops , will add up to less than ideal performance.

You might also seriously consider talking to solar guys involved in house hold setups as they will encounter the problems with interconnections and proper wiring setups.

It would still be a good idea to maintain a separate start battery just in case.
Click to expand...
My bank set up is to pull + from one end and the - from the other. Batts are in pairs, 6 volt.
 
I would keep one dedicated batt or bank for starting the mains and gen. One 4d would be fine. All three can share. Then house bank for everything else, including windlass. Just have an option to tie house and start together for starting redundancy. An ACR for charging house when mains are running. No need to get complicated.
 
Ski in NC said:
I would keep one dedicated batt or bank for starting the mains and gen. One 4d would be fine. All three can share. Then house bank for everything else, including windlass. Just have an option to tie house and start together for starting redundancy. An ACR for charging house when mains are running. No need to get complicated.
Click to expand...



I agree with this. This isn't what I have, but it is the direction that I am thinking about moving.

Keep a separate start battery in case something happens to the house bank. Have the ability to cross-connect so you can start the mains/generator in case there is an issue with the starting bank.

An ACR would work, but so would an echo-charger or Duo-charger. The advantage of the latter is that the batteries can have different charge profiles.
 
Bay Pelican has a 12 battery (six volt Golf Cart) house bank that runs everything. Sole exception a small (Group 24) 12 volt battery under the helm which serves the SSB and the backup VHF. The underhelm battery is isolated from the house bank and has a separate charger. It is also five feet above the water line in the event of flooding.

In ten years with this setup I have never needed the Group 24 battery to start the generator but it will do so. During that time I have started main engines and generators on three other boats with that battery.

Charging of the large house bank is done with two large (100+amp) chargers when on the generator. I use a remote battery switch to divide the bank into two banks so each charger charges six batteries.
 
I appreciate the simplicity of the two alternators, shore power charger all charging the big house/start bank. No switching, no combiners, just one big system. A big bank of GCs will certainly start your Perkins particularly if you never discharge them below 50%.

But you do lose redundancy, not only by accidentally discharging your big house bank so low that it won't start the Perkins, but also system failures.

I would do as you say, but keep the genset start battery independent, assuming that your genset has a DC alternator. Then if something goes wrong, you can always start the generator and charge the house bank with your shore power charger, or worse comes to worse, jumper the genset's DC output to the house bank. It will take forever to bring it up as these alternators are very low output.

Or even better set up the genset with a Group 31 (or one of your 4Ds) starting battery and jumper it to your Perkins if something goes wrong. A Group 31 will easily start a Perkins.

I once had a brand new Mainship and hadn't yet figured out the electrical system when we anchored out overnight. I mistakenly assumed that the starting battery was isolated from the house battery and ran them both down. But I had a separate bow thruster battery which I was able to jumper to the engine and get it started. Even a little bit of redundancy can save your bacon.

David
 
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We have a single engine with 2 alternators with one that charges the house bank (10-T105s) and the other charges the 2 group 31s for the engine. There are independent with no interconnecting switches. I've carried a set of jumper cables for ten years and have never used them on Hobo. I have a 100 amp plus shore charger for the house bank. The start batteries are Optima Yellow Tops. I forget what the self discharge rate is but they've sat for 6 months and have never failed to start our FL SP 135. I did recently install an old Zantrex 40 and hooked it up to the house and start bank when we did redid the engine room just because we had it and have yet to use it.

Our Genertor has another Opitma with no shore side charging and that has never failed to start.

Simples has worked for us. :)
 
Charging

I have a 100 or 140 amp charger, going to check paper work. Also have 2nd Xantrex inverter/charger that I may install. But again that makes thing more complex, but at least I would understand it because I put it in. My Gen Set is 8KW. Installing a continuous duty Alternator with 240Amps and my put another one on other engine. Then there is next year plan of Solar.
Again, my main drain on the hook would be the refrigerator, going to propane at some point, so Microwave.
I am using 6 volt Interstates now, when they fail I will look at AGM or whats new, because of 50% rule as well as the water maintenance.
 
I my Monk 36 Single engine with one alternator, I think mine is 80 amp, and many of her sisters there is a main battery bank consisting of 2 8D batteries which run the house, engine start, bow thruster, and windlass. I have a separate battery to start the generator, this battery is charged only by the generator.
This has worked fine for us, we have a Magnum 2 KW inverter/charger. Days at anchor without cruising we crank up the generator for a while in the AM and again in the evening. Air conditioning when needed must be run off generator or shore power.
We have the Magnum Monitor and a Link monitor so we can see at a glance what the state of the battery bank is.
Some Monk owners have gone to 6 - 6V L/A or AGM batteries (they fit in the existing box) to replace the 8Ds which are very heavy and hard to handle at replacement time, and to get a bit more capacity. I haven't done this but probably will at next battery change out.
 
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We have a single 440 Ah bank of four Oasis carbon foam batteries that double as a starting bank for the twin FL 120s and our house bank. We have a separate group 31 batt for the generator. In 5+ years we've yet to "need" the separate gen battery (as in the house bank was run so low we couldn't start the engines), but it's good to know it's there in case.
 
My KISS electrical arrangement!

House bank as well as twin screw engine starters: Four group 31 deep cycle LA batts in parallel. This bank also works both HD Raritan 12 v Crown toilets and a HD anchor winch.

One group 27 starter LA batt specific for gen set.

One group 27 starter LA batt isolated in separate box and kept at 100% charge as emergency. Long, heavy gauge jumpers just in case!

This simple set up works very well for us! :thumb:
 
Check out Odyssey's pure lead thin plate offering. They can deliver both high starting current and deep cycle (80% DoD) as well. I'm using the PC1800's - 6 in house bank and one each for port and starboard engines. I will soon rotate the start batteries into the house bank, and take a couple of for starting. Connected with Blue Seas ACR's and RBS. I have 4 x Interstate AGM's in the bow for thruster and windlass.

We got rid of god knows how many manual Perko switches - the PO had 2 x banks of 3 x 8D'd, plus 8D start batteries, plus 2 batteries for generator plus 2 batteries for windlass.
 
One question: What would you do if you wake up one day and realize that you did not close the refrigerator door correctly and it ran all the night. You try to depart from yur favorite anchoring site and cannot start your engine...
I would never mix house and starting batteries, just for the sake of being able to start my engine and get back home.

L.
 
Lou_tribal said:
One question: What would you do if you wake up one day and realize that you did not close the refrigerator door correctly and it ran all the night. You try to depart from yur favorite anchoring site and cannot start your engine...
I would never mix house and starting batteries, just for the sake of being able to start my engine and get back home.

L.
Click to expand...

No prob!! See post # 19.
 
We are 12-6Volt golf cart batteries and an AGMGenset start battery and 4-12V AGM Deep Cell 24V Bow thruster and Windlass batteries with a 120v Dual Battery Charger. Full Maretron AC/DC monitoring on all banks. Twin engine Yanmars with 100 amp Balmar alternators and a Balmar Center Fielder so they both, play well together. A 3000 watt Xantrex Model 30 Inverter/charger and 50 amp 220V shore power cord. If I were starting anew I would add a second Inverter/Charger so I could run 220V while underway without the Genset running. Then I would also be ready for Lithium Ion batteries once the price comes down with high charging capabilities. Oh more thing, our inverter/ charger is not in the engine room exposed to all that HEAT.....I think that why the unit has lasted almost 10 years.
 
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Ok I will throw my piece of lead into the mix. My boat came with two 8D start batteries, gen set battery and six 6 volt golf cart batteries in the galley(?).

I eliminated one start battery, ran both engine to a single battery. My thought was I only start one at a time, why have two.

Moved 6 volt house batteries into ER in the space vacated by start battery (mostly).

Left gen set battery alone.

Installed ACR between start and house batteries. Now when mains are running they charge everything except genset. That battery is totally isolated except for 120 volt charger. The idea being if something happens and both start and house go flat, gen set will still start to charge everything. I have a cable that will allow me to connect house and start manually if the start battery goes flat.

I think this way I have made it as simple and foolproof as possible.
 
I'll throw my setup into mix. I have a separate starting battery for each main and the gen. 440AH of house which are completely separate from starting. All batteries can charge from the main eng alts, generator or shore power charger or solar.

Ken
 
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Anyone have thoughts on combining thruster/windlass batteries with engine start batteries?

It seems to me that they all get very little use.
 
dhays said:
Anyone have thoughts on combining thruster/windlass batteries with engine start batteries?

It seems to me that they all get very little use.
Click to expand...

I say "no", not combining anything with engine start.
 
Ski in NC said:
I would keep one dedicated batt or bank for starting the mains and gen. One 4d would be fine. All three can share. Then house bank for everything else, including windlass. Just have an option to tie house and start together for starting redundancy. An ACR for charging house when mains are running. No need to get complicated.
Click to expand...
:thumb:

I like this idea also.

I have one large bank, plus G31 for start.
 
I have 12 6volt batteries that run everything. But I do have a separate battery to start the generator. It all seems to work well and gets charged mostly by 825 watts of solar
 
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