Battery redo - Push (or pull) me in the right direction!

[mncruiser]

Hey all, been a bit but starting to think spring up here in the frozen North. I kind of miss you people!

I have a 2001 Mainship 390, single Yanmar 300 with bow thruster. Also has a reliable Kohler/Yanmar generator. Purchased the boat last spring, here is the existing battery setup:

-FLA 8D - Starting - Bank 1
-FLA 8D - House - Bank 2
-FLA 4D - House - Bank 2
-AGM Group 27 - Bank 3 (dedicated generator battery)

Bank 1 and 2 are able to be combined via standard 1-2-All switch

Things I don't like:
- 8D's are satan's battery, too big and not able to be enclosed properly in my boat
- Thruster and windlass run off bank 1, thruster causes too much voltage drop when used (electronics cut out)
- FLA's, I'm not lazy about much but I don't want FLA's in my boat
- The battery charger, it may be fine but I think it's a cheap camper version installed 5-10 years ago.

Now some setup. We are Lake Superior boaters, out of Bayfield, Wisconsin. Most of our boating for the next 10 years will be local, possible longer trips but isolated. We are rarely out away from our dock for more than 2-3 days. My biggest problem is the fridge. I don't feel like I need more battery capacity on this boat, but may want to supplement solar in the future to compensate for fridge loads. We run the generator when needed and allowed in our area.

What I think I want:
- AGM's but not 8D's. Some manageable size.
- Dedicated bank for thruster and windlass. This bank has to be able to be charged by main engine alternator, I suppose I could be talked into using generator for this but don't want to. But I probably should use the generator more..has less than 200 hours on it....not sure here.
- Similar capacities - 240ah for house. 160ah for starting. Unsure what I need for thruster/windlass.
- New charger. I read about some new DC-DC charging thing that sounded like a dream, need more research here. I'd love to know what the charger is doing. Last boat had a Xantrex with remote panel I put in, worked well.

My major questions:
- Any of the above wants silly or a waste or i'm misguided on something?
- Stick with 12V or go 6V for the batteries? I bought all the big crimping tools (yep the spendy ones) in preparation for this. Would like to re-use what I can but ready to buy some wire and get crimping.
- Do I need to plan to be able to combine my new thruster/windlass bank with the others?
- What else am I not thinking of?

Thank you!

mncruiser

 

[Solly]

I'm a fan of all batteries being the same type and size. Easier for charging and if you have to connect the banks. I have 2 group 29 deep cycle each for house and start with the 1-2 combine switch. I'd like to have another 1 separate for the thruster and windlass some day. With maybe an auto charging relay to the start bank for charging. Thruster and windlass are a heavy draw but short duration.
About all we use on the hook is the fridge and so far it's been fine for 2-3 days.
I have a small (10a), 2 bank, smart charger for on the dock. It has plenty of time between trips to keep everything charged up.
I don't have a good way to measure use so no idea how hard we do use the batteries.

 

[RCook]

Our NT 37, with single Cummins 6BTA-5.9-M3 330hp, has all g31 AGM’s, 105ah each, except for the generator. Four g31’s for house, two for windlass and bow thruster, and two more for main engine start. One more yet for the stern thruster. Charging from alternator or from inverter/charger goes to house bank. Start, windlass and thruster batts are charged via ACR’s. House and start can be combined with a switch, though I've never had to do so.

When I replaced all the old stuff ~5 years ago, I redid all the cables (2/0) carefully with with quality lugs, big crimper, hot glue heat shrink, and dielectric grease on each connection. (See article "Making Your Own Battery Cables" by TF member CMS on marinehowto.com). Cables to starter and thrusters are all quite short. Works like a charm, even with lengthy use of thrusters.

 

[Bacchus]

existing battery setup:

-FLA 8D - Starting - Bank 1
-FLA 8D - House - Bank 2
-FLA 4D - House - Bank 2
-AGM Group 27 - Bank 3 (dedicated generator battery)

Bank 1 and 2 are able to be combined via standard 1-2-All switch
IF I UNDERSTAND CORRECTLY THIS IS WHAT MY MS34 HAD AND EITHER BANK 1 OR 2 REALLY SERVES BOTH HOUSE & START??

Things I don't like:
- 8D's are satan's battery, too big and not able to be enclosed properly in my boat
AGREE AND WANT TO GET RID OF MINE AS WELL
- Thruster and windlass run off bank 1, thruster causes too much voltage drop when used (electronics cut out)
IM ASSUMING BASED ON MINE AND NOTE ABOVE THIS IS BECAUSE BANKS 1 & 2 ARE NOT REALKY SERVING SEPARATE NEEDS BUT MERELY SELECTED VIA THE SW AND SERVE BOTH START & HOUSE (ELECTRONICS )
- FLA's, I'm not lazy about much but I don't want FLA's in my boat
ALSO AGREE AND HAVEVANDVWILLVSTAY W AGM
- The battery charger, it may be fine but I think it's a cheap camper version installed 5-10 years ago.

What I think I want:
- AGM's but not 8D's. Some manageable size.
- Dedicated bank for thruster and windlass. This bank has to be able to be charged by main engine alternator, I suppose I could be talked into using generator for this but don't want to. But I probably should use the generator more..has less than 200 hours on it....not sure here.
WHY NOT COMBINE THRUSTER /WINDLASS W START? A PAIR GP31 SHOULD HANDLE BOTH ESPECIALLY WITH ENG RUNNING & ALT SUPPLEMENTING
- Similar capacities - 240ah for house. 160ah for starting. Unsure what I need for thruster/windlass.
- New charger. I read about some new DC-DC charging thing that sounded like a dream, need more research here. I'd love to know what the charger is doing. Last boat had a Xantrex with remote panel I put in, worked well.
I HAVE ONLY READ ABOUT DC-DC CHARGERS BUT MY IMPRESSION IS THAT THEY ARE ADVANATAGEOUS WHEN DEALING W DIFFERENT CHEMUSTRIES, ESPECIALLY LiFePo. ANY MIDERN MULTI BANK CHARGER SHOULD WORK OK WHERE ALL SAME CHEMISTRIES. SEE MY NOTES & WEBSITE PROJECTS WHERE RELAY WAS INSTALLED FOR ALT CHARGING OF MULTI BANKS

My major questions:
- Any of the above wants silly or a waste or i'm misguided on something?
- Stick with 12V or go 6V for the batteries? I bought all the big crimping tools (yep the spendy ones) in preparation for this. Would like to re-use what I can but ready to buy some wire and get crimping.
- Do I need to plan to be able to combine my new thruster/windlass bank with the others?
- What else am I not thinking of?

Thank you!

mncruiser

I have a MS 34HT single Yan 370 B& S thrusters and gen and will share what I have / have done and why to provide good for thought. Lots of ways to do it so don't necessarily think any one is best... certainly not for everyone.

Original set- up had 1 8D for B&S thrusters, 2 8Ds for combined start & house and a gp 24 for gen. All FLA. I could not charge during winter storage and could not bring 8Ds home for winter maint charge. When replacing I switched to AGM 8Ds but agree with you and will NOT buy another 8D.

Mine had MS OEM diode isolators for both engb alt and shore charging. I wanted to eliminate both and details of what I did and why can be found on Bacchus website- Projects Pg 4 - Alt & Shore Charging Mods.

I didn't like having eng start & house combined even though MS included a 1-2-all Sw to manage the 2 battys/banks and at times has electronics drop out when starting eng.
Recently I moved my eng start to the thruster bank. Shorter cable run and I figured thruster use would always be with eng alt running. I now have a pure house bank and have combined the 2 8Ds. I also added a Balmar SmartGauge to monitor house bank V & SOC and it provides thruster bank V to give me an indication of batty health.

I have also started planning for what to replace the 8Ds with when the time comes. I initially thought I'd use AGM GP31s for hi amp draw start & thruster bank and AGM GC2s for house bank. I queried East Penn and Trojan about the +/- of the above. I got consistent responses that both would serve equally well in either application which was a learning on my part. Apparently the plate design differences and pros/ cons for start & deep cycle don't hold true for AGM.

As a result my current thinking is why bother mixing GP31 for start and GC2 for house? And pretty sure I will simply use all AGM GP31s... 2 for start & thruster and 4 for house banks. My gen has an alt and it's own AGM GP24 which I will leave as is. I did install a 1-2-all sw for the gen (replacing a simple on/off) and a jumper to my house Sw so I have a back up for gen if necessary (never needed or used yet). The East Penn Duracell GP31s from SamsClub have both auto post and yhreaded stud attachments so my plan us to use existing main + & - cables and simply add new inter- batty jumpers using ring terminals to for the larger banks. I will follow recommendations for balancing charging & draw for multi batty banks.
Having them all (6) the same GP31 should give me some flexibility when / if some batty are showing weakness... all same size, chemistry & age... if 1 orc2 weak I'd put new on thruster / start pair and use remaining one for house. If 3-4 getting weak I'd do the opposite putting new in house & use older useful for start as long as they were testing OK.

If any of above is not clear or you have questions let me know.

 

[ranger58sb]

-FLA 8D - Starting - Bank 1
-FLA 8D - House - Bank 2
-FLA 4D - House - Bank 2
-AGM Group 27 - Bank 3 (dedicated generator battery)

Bank 1 and 2 are able to be combined via standard 1-2-All switch

Things I don't like:
- 8D's are satan's battery, too big and not able to be enclosed properly in my boat
- Thruster and windlass run off bank 1, thruster causes too much voltage drop when used (electronics cut out)
- FLA's, I'm not lazy about much but I don't want FLA's in my boat
- The battery charger, it may be fine but I think it's a cheap camper version installed 5-10 years ago.

In general, 12V Group 31s can be a bit more manageable size, as are 6V GC2. I had to plot out available space before I could decide what (size/voltage) batteries for what purpose might fit where.

Think I'd prefer one large house bank to two smaller ones.

You could move your electronics to a house bank to avoid that whole voltage drop/cut out thing.

I had good luck with Odyssey 12V PC-2150 G31s AGMs and with Lifeline 6V GPL-4CT AGMs. Can't speak to other brands.

Yes, the charger should be best matched to the batteries, so you can match actual charger supply voltages with battery voltage recommendations.

-Chris

 

[mncruiser]

Mine had MS OEM diode isolators for both engb alt and shore charging. I wanted to eliminate both and details of what I did and why can be found on Bacchus website- Projects Pg 4 - Alt & Shore Charging Mods.

Thanks for the reply. How did you identify the OEM isolators? I'm under snow and shrink wrap so can't look. The battery systems were not a major issue last season, had potty and couch issues to deal with. I know what needs priority! I kind of can't remember what was there.

I was initially thinking more complex, but I kind of like the idea of the Group 31 AGM's in place of the 8D's and 4d, then move the electronics off the starting bank. I bet I could preserve a bunch of the existing wiring and just do the interconnects like you mentioned.

I also like the Sterling device you put in. Thanks for the great site, I've used it many times! I'm not sure, but also think I have some fusing to do. I don't recall the proper fuses being there.

What did you use for battery trays/enclosures?

I bought AGM''s for the last boat, all the Sam's Duracell ones. Worked great. But every Sam's within 200 miles of here has nothing right now.

Thanks

mncruiser

 

[mncruiser]

In general, 12V Group 31s can be a bit more manageable size, as are 6V GC2. I had to plot out available space before I could decide what (size/voltage) batteries for what purpose might fit where.

Think I'd prefer one large house bank to two smaller ones.

You could move your electronics to a house bank to avoid that whole voltage drop/cut out thing.

I had good luck with Odyssey 12V PC-2150 G31s AGMs and with Lifeline 6V GPL-4CT AGMs. Can't speak to other brands.

Yes, the charger should be best matched to the batteries, so you can match actual charger supply voltages with battery voltage recommendations.

-Chris

Kind of where I migrated my thinking to. Now just need to find some good batteries! Thanks for the reply!

 

[mncruiser]

Our NT 37, with single Cummins 6BTA-5.9-M3 330hp, has all g31 AGM’s, 105ah each, except for the generator. Four g31’s for house, two for windlass and bow thruster, and two more for main engine start. One more yet for the stern thruster. Charging from alternator or from inverter/charger goes to house bank. Start, windlass and thruster batts are charged via ACR’s. House and start can be combined with a switch, though I've never had to do so.

When I replaced all the old stuff ~5 years ago, I redid all the cables (2/0) carefully with with quality lugs, big crimper, hot glue heat shrink, and dielectric grease on each connection. (See article "Making Your Own Battery Cables" by TF member CMS on marinehowto.com). Cables to starter and thrusters are all quite short. Works like a charm, even with lengthy use of thrusters.

Thanks Richard. I've referenced that site many times, where I found all the links to buy the right tools! Thanks again for the advice!

 

[Bacchus]

Thanks for the reply. How did you identify the OEM isolators?

I was initially thinking more complex, but I kind of like the idea of the Group 31 AGM's in place of the 8D's and 4d, then move the electronics off the starting bank. I bet I could preserve a bunch of the existing wiring and just do the interconnects like you mentioned.

I also like the Sterling device you put in.

What did you use for battery trays/enclosures?

I bought AGM''s for the last boat, all the Sam's Duracell ones. Worked great. But every Sam's within 200 miles of here has nothing right now.

Thanks
mncruiser

I'll attach an isolator pic - I had one on the stringer right under the Alt. When I removed it I used the same Alt output cable to the starter and did my new runs to the Sterling CVSR from there.
I also had an isolator mounted near the shore charger to split one of the three charger banks to service 2 banks for a total of 4.
I didn't like charging very different size batty from same charger - GP24 & 8Ds - When I removed that one I just left the gen alt charge the gen batty and I used the 3 charger banks to charge one 8D each (2 - house + 1 thruster / start) I changed the gen batty sw from on-off to 1-2-all-off which was simple same footprint & bolt holes. Just added a short jumper to house batty Sw so I have emerg'y back up to start gen. (has never been needed but I do use it to top off gen batty from shore charger & house bank if I haven't run gen in a while.

When I combined my house battys I reused one of the 4/0 cables for my "new" starter connection form thruster batty - overkill but no V drop w/ shorter / larger cable to batty.

The Sterling CVSR has worked well and has several modes you can use to control it. I looked at some others but contacted their tech guys as I was concerned about running thrusters when banks combined if it would see a hi amp pulse from house to thruster bank and the response I got was their units would not be recommended - Sterling & Rod from CMS (TF Commercial member and great guy) reviewed my schematics and said it would be fine. I bought it from Rod but his online store is down now as he is out with medical issue.

Re Batty trays - I still have my AGM 8Ds so using my OEM MS trays. STill looking & deciding buying some GP31 trays or just building a retaining system w/ alum angle (Front & back of each bank and using strap hold downs)

Agree if your electronics are on the start batty move it to house - I wasn't sure if you were like my MS combined start / house? 2 battys w/ 1-2-all Sw but serves both needs or something different. If so that's exactly why I moved the starter cable and left electronics on house. I also didn't bother moving any of the engine controls / electronics just the hi amp starter cable..

What I have may not be everyone's first choice but it seems to work well for us and our style of cruising. We don't tend to anchor for more than a few days but have done 60+ days cruising with mix of anchor, lock walls w/o power and marinas and had no problems. I usually ran gen for an hour or so at night for cooking dinner and hour in AM for coffee & b'fast.
Let me know if any other questions.

 

[mncruiser]

.

Let me know if any other questions.

Thanks for all the great info. Will have to do some hunting when I can get back on the boat.

I ran across an article in a boating mag a few months ago, it had this in it: Digital Mobile Charge130 alternator to battery on-the-water charging system-

https://www.promariner.com/en/p/05513/130-Amp-Alt-Btery-12V

It sounds like an ideal solution. I need to contact them and do some research about loads and related things.

Curious what you think of it.

Thanks

mncruiser

 

[BruceK]

Nothing like 8Ds to cause dread about replacement like for like!
I searched your charger, it seems a relatively modern multistage 3 channel model. Maybe check it out before replacing.
https://www.progressivedyn.com/marine-2019/pd2160-60-amp-convertercharger/

 

[Scottwb96]

Whatever you do... DITCH the 8D's! ! ! Group 31's will be more than fine for a replacement. The next part you need to decide is how big and how complicated you want to go.
You could do a fairly "simple" (hehe) swap out of all batteries to G-31's and keep you existing config. Just need to update regulator settings as well as main charger settings.
I am switching out my Magnum charger/inverter for a different brand (Victron) only so that I can standardize all the chargers (5) across my boat (long story). So if you're also looking for a new 12v 2,800w inverter with ALL the accessory components (including AGS) let me know...

 

[Bacchus]

Thanks for all the great info. Will have to do some hunting when I can get back on the boat.

I ran across an article in a boating mag a few months ago, it had this in it: Digital Mobile Charge130 alternator to battery on-the-water charging system-

https://www.promariner.com/en/p/05513/130-Amp-Alt-Btery-12V

It sounds like an ideal solution. I need to contact them and do some research about loads and related things.

Curious what you think of it.

Thanks

mncruiser

I would have a system schematic and ask them to review it.
They didn't have that when I was looking but it was their ProIso charge unit that I was first thinking if. They reviewed my schematic and my query re potential back feed of hi amps when thrusters activated and banks were connected. At that time the Sterling and ProMariner units were about the same $.

 

[ranger58sb]

At that time the Sterling and ProMariner units were about the same $.

Many (most? all?) Sterling and ProMariner products are exactly the same units.

-Chris

 

[Bacchus]

Many (most? all?) Sterling and ProMariner products are exactly the same units.

-Chris

At least when I was doing my mods the Sterling CVSR was different than the ProIso Charge in that the Sterling was capable of disconnecting under hi amp draws. Otherwise same functionality.