Battery and Solar Questions.

[Glenn]

2016 Cutwater 30CB - New to me

My house batteries die within an hour or two of being on the water. They have a date of 9/20, so I am guessing 2020 or 5 years old now.
Current Battery x 4 = 12V 725CCA 890MCA 100Ah 190RC Deka Dual Purpose Marine Battery

I was thinking of replacing them with AGM batteries from Canadian Tire.
MOTOMASTER NAUTILUS AGM Group Size 31 Battery 1000 marine crank amps, 105 amp hours, 200 minutes reserve capacity

I also have solar panels that come with the boat. I am not able to tell if it is charging the house batteries.

The sun saver duo has all the dip switches all on off, which means 90/10%. I guess 90% to the house? #3 changes this to 50/50

I was trying to learn the Remote Meter to see if I can tell if they are getting any charge, I could not tell. After pushing a few buttons, the screen went mostly blank.

Any advice is appreciated.

Thanks
Glenn

 

[Eagle 2]

2016 Cutwater 30CB - New to me

My house batteries die within an hour or two of being on the water. They have a date of 9/20, so I am guessing 2020 or 5 years old now.
Current Battery x 4 = 12V 725CCA 890MCA 100Ah 190RC Deka Dual Purpose Marine Battery

I was thinking of replacing them with AGM batteries from Canadian Tire.
MOTOMASTER NAUTILUS AGM Group Size 31 Battery 1000 marine crank amps, 105 amp hours, 200 minutes reserve capacity

I also have solar panels that come with the boat. I am not able to tell if it is charging the house batteries.

The sun saver duo has all the dip switches all on off, which means 90/10%. I guess 90% to the house? #3 changes this to 50/50

I was trying to learn the Remote Meter to see if I can tell if they are getting any charge, I could not tell. After pushing a few buttons, the screen went mostly blank.

Any advice is appreciated.View attachment 25934

Thanks
Glenn

 

[Eagle 2]

Glenn, I just bought the same exact boat and year, so I’ll be following your progress here. Mine has 4 Universal 210 amp batteries, 12/19 date. Mine goes in the water at the end of the week, so hoping I can milk them till winter, then I’ll be replacing them with the Mighty Max 210 amp AGMs. Having installed a Renogy system on my former Mainship 30, I was very impressed with the results, and will probably adding those also this winter, 2/200 Flex panels to the Bimini on the CB, and a separate 40 amp MPPT. This should give me all the power we need, as we will be keeping it on a mooring at Catalina Island all summer. I’ll update when the project starts!

 

[Cutwater28GG]

For the house batteries you don’t need cca. That’s why I stuck with the universal batteries that the boat ships with. They are good value perform reasonably well and are delivered for free form places like Amazon or Home Depot who ever has them in stock. I get the 110aH versions.

Many folks have pulled out the sunsaver duo unit and replaced with a victron 100/30 solar mppt charger. It’s more efficient and easier to monitor via your phone. It also gives you room to upgrade the panel to 400w.
Lots of threads on this.

I did install a different battery for engine start as the universals don’t have the cca. I went with an x2 and it’s been great. It’s twice the price of the universals. Hence why I don’t install it for all the batteries.

What you need to watch is the battery charging voltages and make sure they are close across barriers installed as the alternator and shore power charger is not that configurable.

 

[SKing]

2 seasons ago I reinvested in AGMs. We use our boat at anchor durring the summer. I would only recommend AGMs if you don't plan on being at anchor for more than 1 to 2 nights. For the following reasons.

(C30CB
Fresh batteries Lifeline AGMs. (4×125amp hrs= 500 amp hrs, only 250 amp hrs usable)
Factory solar panel
Victron Shunt
Victron solar controller)

We draw 120-140 amo hrs a day.
Recharging starts at 60 amp hrs when the battery bank is 75% or less but as the batteries charge they accept less energy so is starts dropping as they charge and end up at 10 amps near the end. This means that you need to run the boat for 3-4 hours to get charged back up after 1 night. (AGMs don't like partial charges)

The best we have received from our solar is 50 amp hrs on a special day where the panel faced full sun all day with no shadow

The result of all this info is that 2 days at anchor followed by a 5-6 hrs run or plugged in overnight is the best case scenario.

If I had to do it again I would convert instead of sticking with AGMs for our desired usage of the boat. If your usage fits the limitations of AGMs save the money from converting and spend it on fule.

 

[abastos]

Great thread. Thanks for sharing your experience SKing

We have our new-to-us 2018 C-30S for 3 months now and I don't know for how long my house batteries can feed the boat. I have 4x Discover EV31A-A AGM 110 AMPs each installed in 2022. In theory ~200 amps available (assuming they are working properly), but it is hard to monitor.

I am planning to contract a boat electrician to install the Victron Shunt and Victron Solar Controller to have a way to monitor the house bank consumption. My plan is to go to LiFePO4 in the future and create a large bank, something about 600-800Ah.

 

[Glenn]

Thanks for all the replies! I see new batteries in my near future and a small generator if travelling!

 

[SKing]

I am planning to contract a boat electrician to install the Victron Shunt and Victron Solar Controller to have a way to monitor the house bank consumption.

The shunt and solar controller were worth every penny spent on them. Without the true readouts it was a guessing game on what was happening electrically. And they are still needed if you upgrade anyway.

 

[SKing]

Today I jotted down info while running the boat. We had been at anchor 2 days.

started motor at 7:30am
Charging @ 90 amp
500 amp battery bank @ (total used -250 amp hours)
75 amp @ 8:30
60 amps @ 9:00
53 amps @ 9:08
43 amps @ 9:32 (-111 amp hours)
34 amps 10:08 (-89)
28 amps 10:43 (-72 Amp hrs)
24 amps @ 11:07 (-62 amp hrs)
20 @ 11:47 (-47 amp hrs)
18 amp 12:10 (-0 amp hrs)

It will still continue to charge at this lower amperage to top off the Battery bank.

-250 amp hours, to charged was 4hr 40 min

As you can see the batteries will not accept the full 90 amps that the alternator puts out. So charging time is longer than with Lithium batteries.

 

[Cutwater28GG]

what you will also find SKing is the last part of charging is the most important in really getting the batteries to 100%SOC. Most batteries don't ever get there. usually through two reasons
1. not enough time in the last phase
2. too low a voltage to get the batteries to full SOC and many chargers are not good at this.

if you are only measuring SOC based on amp's drawn down - you need to be careful you are actually starting at 100%SOC as you might find you are hurting the batteries by going into a deeper state of discharge

 

[abastos]

Today I jotted down info while running the boat. We had been at anchor 2 days.

started motor at 7:30am
Charging @ 90 amp
500 amp battery bank @ (total used -250 amp hours)
75 amp @ 8:30
60 amps @ 9:00
53 amps @ 9:08
43 amps @ 9:32 (-111 amp hours)
34 amps 10:08 (-89)
28 amps 10:43 (-72 Amp hrs)
24 amps @ 11:07 (-62 amp hrs)
20 @ 11:47 (-47 amp hrs)
18 amp 12:10 (-0 amp hrs)

It will still continue to charge at this lower amperage to top off the Battery bank.

-250 amp hours, to charged was 4hr 40 min

As you can see the batteries will not accept the full 90 amps that the alternator puts out. So charging time is longer than with Lithium batteries.

SKing, charging at 90 amp with the engine at what RPM rate? Idle? I was trying to find how much amps-hours the D6 engine's alternator put when the boat is in idle.

 

[SKing]

I was running slow so as we wandered through new territory, 1400 or less for the whole time.

 

[SKing]

what you will also find SKing is the last part of charging is the most important in really getting the batteries to 100%SOC. Most batteries don't ever get there. usually through two reasons
1. not enough time in the last phase
2. too low a voltage to get the batteries to full SOC and many chargers are not good at this.

if you are only measuring SOC based on amp's drawn down - you need to be careful you are actually starting at 100%SOC as you might find you are hurting the batteries by going into a deeper state of discharge

I've reset fully charged after being plugged into shore power for several days and nolonger showing charging current. I haven't done the reading on charging voltages etc yet. Just relying on the factory charger settings.