6VDC Golf Cart Battery Question

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Just to finish off

Last week I scrapped the old battery Isolator and went with a new ProMariner unit that is completely electronic and very easy to install. The old isolator need a diode kit installed on the start batteries and the kit was no longer available. The new one allows two alternator inputs and 4 battery outputs. The system also prioritizes the start batteries before charging your house batteries.

No I need to go get 4 more batteries (8 total) and my system is complete

Here is what I installed:

http://promariner.com/products/prolsocharge-series/
 

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Hard to tell in a picture but those cables look kind of small for the kind of amps you are talking about.
 
Nice install Tom. I am really impressed with how white and clean your ER is. I have a Promariner setup on our trawler. It is working great so far. I am in the middle of installing three 150 watt semi-flexible solar panels on our bimini. I can wait till its done so I can share the completed project with the forum.
 

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Hard to tell in a picture but those cables look kind of small for the kind of amps you are talking about.

Which wires are you refering too? I followed the manufactures recommendations and also went one step above what they recommended. For the battery cabled, I used #2 wire and the wires coming off the alternator are #6 and the ignition sensing wires are #12.
 
Nice install Tom. I am really impressed with how white and clean your ER is. I have a Promariner setup on our trawler. It is working great so far. I am in the middle of installing three 150 watt semi-flexible solar panels on our bimini. I can wait till its done so I can share the completed project with the forum.

Thanks. It is starting to get crowded down there. I too have been thinking about solar, but I am not part of the "don't run your Genny" crowd. If I need power I start my genny, that is what it is there for. I will tell you my genny is very very quit, so you can bearly hear it.

BTW nice job on your too.
 
Nice install Tom. I am really impressed with how white and clean your ER is. I have a Promariner setup on our trawler. It is working great so far. I am in the middle of installing three 150 watt semi-flexible solar panels on our bimini. I can wait till its done so I can share the completed project with the forum.

I am very interested in how your solar project comes out. Being on a mooring or on the hook most of the time, I want to find a better way of keeping the house bank charged without having to run the genny all the time. Every time I look at various ways to get (or keep) the house bank charged, I keep going back to solar as being the most efficient.

Ken
 
I am very interested in how your solar project comes out. Being on a mooring or on the hook most of the time, I want to find a better way of keeping the house bank charged without having to run the genny all the time. Every time I look at various ways to get (or keep) the house bank charged, I keep going back to solar as being the most efficient.

Ken
Just do it, you won`t regret it. It`s the easy way to keep batteries fully charged, and to cram that last 15% of charge into the battery, by relentless charging, via a good controller of course.
 
Solar does a great job of keeping batteries up, as the time required for that last 10%-15% of charge is daily and silent.

Solars problem is it is seldom large enough to handle the huge load from refrigeration.

Topping batts up or creating 200AH a day are two different requirements.

We have no shore power on out boat , the solar or use of the vessel keep everything fine , for multiple seasons.

Refrigeration is Propane .
 
Thanks. It is starting to get crowded down there. I too have been thinking about solar, but I am not part of the "don't run your Genny" crowd. If I need power I start my genny, that is what it is there for.

Solar panels were added to Bay Pelican as 1) cost savings device, payback in saved diesel, maintenance already has paid for them, 2) backup with the solar panels and wind generator I can stay off the dock if the genset goes down, and 3) length of time between generator runs - we can leave the boat for 12/14 hours to tour without worrying about the power level.
 
Tom, what do you have now as your 12V house bank in AH? 832? More?
 
Tom, what do you have now as your 12V house bank in AH? 832? More?

I believe it is now setting at 832AH. Each battery is rated at 208AH. A 4 battery bank, two connected in series to make 12Vdc (208AH), then each connected in parallel which is 416AH per bank. 2 banks equals 832AH.

So right now I have two battery boxes that hold four 6Vdc batteries total. Not sure if I will need more or not. we will see how this setup performs this summer.

I have a 50amp battery charger that only charges the house banks when the genny or shore power is used. When the main engines are running they pump 102amps to the house batteries once the start batteries are charged.
 
"I have a 50amp battery charger that only charges the house banks when the genny or shore power is used. When the main engines are running they pump 102amps to the house batteries once the start batteries are charged."

While USING juice the modern setup is to gang the bank to the largest configuration.

CHARGING when running with 2 alts ,isolating the bank into 2 groups and letting one engine charge 1/2 the bank , the other engine charging the other half will speed up the charge time .

A "smart V regulator " will help shorten the time as well.
 
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All "juice" from the two engines are sent to the "smart Isolator" which determines which bank and how much charge to send.
 
One simple foolproof method is to copy RV tech.

An $18.00 relay closes when the engine is operating and charges the house from the engines alt.

This solves the hassle of voltage drop thru an isolator , and transistor hassles.
 
One simple foolproof method is to copy RV tech.

An $18.00 relay closes when the engine is operating and charges the house from the engines alt.

This solves the hassle of voltage drop thru an isolator , and transistor hassles.

The isolator I have does not have any voltage drop unlike the old styles.
 
I believe it is now setting at 832AH. Each battery is rated at 208AH. A 4 battery bank, two connected in series to make 12Vdc (208AH), then each connected in parallel which is 416AH per bank. 2 banks equals 832AH.

Actually, when 2 batteries are connected in series, they retain the same amp hour rating as a single battery. Then connecting two pairs of batteries in parallel, the amp hour ratings are added. So each of your pairs has a rating of 12 volts with 208 amp-hour Tied together in parallel the two pairs of batteries have a rating of 12 volts with 416 amp-hours.

Golf Cart batteries are a good way to go as they are built to be deeply discharged and recharged for many cycles.
 
I believe it is now setting at 832AH. Each battery is rated at 208AH. A 4 battery bank, two connected in series to make 12Vdc (208AH), then each connected in parallel which is 416AH per bank. 2 banks equals 832AH.
Actually, when 2 batteries are connected in series, they retain the same amp hour rating as a single battery. Then connecting two pairs of batteries in parallel, the amp hour ratings are added. So each of your pairs has a rating of 12 volts with 208 amp-hour Tied together in parallel the two pairs of batteries have a rating of 12 volts with 416 amp-hours.

Golf Cart batteries are a good way to go as they are built to be deeply discharged and recharged for many cycles.

Reread OP - 2 banks of 4-6V batty's are indeed 832AH
 
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So right now I have two battery boxes that hold four 6Vdc batteries total. Not sure if I will need more or not. we will see how this setup performs this summer.

I thought "four 6Vdc batteries total" was pretty clear. If I misunderstood, I apologize.
 
I was confused, too, until I reread post #1. He has 8 6v batteries in series-parallel providing 12V and 832AH (208 x 4). I got confused by post #25 when 1680 AH was being tossed around.
 
"Golf Cart batteries are a good way to go as they are built to be deeply discharged and recharged for many cycles"

This is true , BUT the number of charge discharge cycles depends on the depth of discharge , and how long it stays discharged.

Before purchasing new batts ,

installing a SOC meter and learning how to nurse the old house set will teach the basics on getting 6-7 years out of the house rather than 3-4 years.
 
Hi Tom

Looks pretty good. I went through the same exercise a few years ago on our boat.

I have been using that ProMariner ProIsoCharge device for several years. It takes the output of the two 52-amp alternators, combines them and sends the output to what ever battery bank (up to four) demand it. It has worked very well to recharge the house bank over four (or more) hour transit from one anchorage to the next.

The only thing I do not like about it is that it does not actually provide any kind of "charge control" like the AC-powered battery charger does. I have to be very watchful of the battery water levels while cruising to make sure they stay topped off. More recently I came across this DC-Powered multi-stage battery charger from Sterling Power (the same folks who designed the ProMariner chargers). I am seriously thinking of replacing the ProIsoCharge device with the charger to get that multistage charging capability while underway.

Marty....................
 
Hi Tom

Looks pretty good. I went through the same exercise a few years ago on our boat.

I have been using that ProMariner ProIsoCharge device for several years. It takes the output of the two 52-amp alternators, combines them and sends the output to what ever battery bank (up to four) demand it. It has worked very well to recharge the house bank over four (or more) hour transit from one anchorage to the next.

The only thing I do not like about it is that it does not actually provide any kind of "charge control" like the AC-powered battery charger does. I have to be very watchful of the battery water levels while cruising to make sure they stay topped off. More recently I came across this DC-Powered multi-stage battery charger from Sterling Power (the same folks who designed the ProMariner chargers). I am seriously thinking of replacing the ProIsoCharge device with the charger to get that multistage charging capability while underway.

Marty....................

Thanks Marty! I will keep an eye on it.......
 
from Sterling Power (the same folks who designed the ProMariner chargers).

These do work but some make HUGE RFI , not great for an occupied boat.
 
from Sterling Power (the same folks who designed the ProMariner chargers).

These do work but some make HUGE RFI , not great for an occupied boat.

Seriously? Never came across anything about that while researching it? Any references?

Marty..........................
 
Seriously? Never came across anything about that while researching it? Any references?

Only 4 that went in the trash can, but that was 5 years ago so maybe,,,,,,
 
Alaskan Sea-Duction: A nice , neat installation. If not already present, make sure the lids on the battery boxes are vented at the apex or top of the lid, cut outs on the sides are ineffective unless they reach the top surface of the lid. Shoe box lid designs like this trap hydrogen in an envelope above the battery, if a spark is created by a loose connection it could result in an explosion.

Also, as an aside, your primary fuel filters are the automotive rather than UL marine or "MA" version (it was very common, fortunately now less so although not unheard of, for boat builders to use these filters), they lack heat shields and metallic drain valves. This is an easy retrofit and worth the trouble as it will provide the filter with the flame resistance recommended by UL and ABYC. This article explains the differences between MA and non-MA units Primary Fuel Filters | | PassageMaker

Excerpt, "Regardless of the brand or model, among the most common installation flaws that I encounter when inspecting a vessel involves the filter’s fire resistance. Unbeknownst to many boat owners, and some boat builders and yards, while they may look similar in appearance, there is a decided difference between filters destined for industrial and automotive applications versus those specifically designed for marine, and therefore fire resistant, use."
 
Alaskan Sea-Duction: A nice , neat installation. If not already present, make sure the lids on the battery boxes are vented at the apex or top of the lid, cut outs on the sides are ineffective unless they reach the top surface of the lid. Shoe box lid designs like this trap hydrogen in an envelope above the battery, if a spark is created by a loose connection it could result in an explosion.

Also, as an aside, your primary fuel filters are the automotive rather than UL marine or "MA" version (it was very common, fortunately now less so although not unheard of, for boat builders to use these filters), they lack heat shields and metallic drain valves. This is an easy retrofit and worth the trouble as it will provide the filter with the flame resistance recommended by UL and ABYC. This article explains the differences between MA and non-MA units Primary Fuel Filters | | PassageMaker

Excerpt, "Regardless of the brand or model, among the most common installation flaws that I encounter when inspecting a vessel involves the filter’s fire resistance. Unbeknownst to many boat owners, and some boat builders and yards, while they may look similar in appearance, there is a decided difference between filters destined for industrial and automotive applications versus those specifically designed for marine, and therefore fire resistant, use."


Thank you Steve for your advice, especially the battery boxes. I guess I could drill a hole in the top lid.

However, the fuel filters (the Racors 900 FG I am assuming) met all U.S. required standards when it was manufactured back in 1988. If the filters are replaced I will make sure the meet ABYC suggested standards.

In my opinion, ABYC does not set marine law or standards. They only have suggested standards. Hell you can't get a copy of the standards unless you pay for them. If ABYC had its way, every boat owner would be required to follow their suggested standards retroactively each and every year they come out with some new fangled idea from the ABYC staff.
 

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