charging batteries

[terraplane]

OK, another one from the Dunce's Corner..(we should have our separate site).

So, i'm on the hook. I want to charge the batteries using the Mase 2.5 genset. What is the procedure
(R 25, hull 52)How long do you have to keep the genset going to get a charge.
I usually don't run the refrigerator all night, just lights, music.

tom

 

[Andrew Custis]

That will of coarse depend on your battery levels. Typically your engine and thruster are going to stay near full as your house is going to be the main one needing charging. I would just keep an eye on your house level by using your DC volt meter and switching it to the #3 selection. If it gets down to around 12 volts then I would fire up the genset and let it charge for about an hour. Just a guestimate as thats a tough one to say.

 

[Stella Maris]

Tom,
While on the hook on Solitude we keep the battery's topped off by using two small solar panels that are mounted on the sports rack. I run the cord down through the hatch over the helm and plug into the cigarette lighter. We run the refrigerator and stereo all day with little or no discharge on the house bank.

The solar panels are removed for towing as the simply drop into the permanently installed mount.

 

[terraplane]

Dave and Maureen,

Thanks for the solar idea. Typically I am on the hook one night of three...I have a string of free docks around the Bay and also use some marinas. But i'd like to be able to keep refrig. and lights up...Will look into the solar panels.
West Marine?

tom (terraplane)

 

[captd]

Tom,
It will take more then a hour of charging to get your batteries to full charge. You will discharge for hours and it will take hours to bring them back to full charge. But with your boating plan it should be no problem if you are plugging in every other day or so. Be sure to hit the charge switch after starting you genset. The fridge takes 4 amps and those small trickle charge solar panels won't be enough. It will help keep your batteries up with no power draw when the boat is in storage. But it all helps.
I have found the two 130 watt panels keep the fridge going on land or in the water. We watch Tv and use computor, and lights every night. The size of your converter has a lot to do with the bulk charge of 80 % The last 20 will go in a lot slower.
captd

Fridge draws 4 amps. 50% of the time. It cycles on and off.= averages two amps

 

[terraplane]

OK, getting varied responses on battery charging...re: genset.
A typical week for me might be three nights plugged in and four on the hook.
Often I use a super insulated cooler for stuff, and just turn off the refrig. at night
Don't use a computer on board .
Lights to read and music on stereo.

I have the stock factory batteries.

Should i consider upgrading the house battery? All batteries?

"This is a message from the Dunce's Corner"

Thanks, Tom

 

[CaptMac]

No easy answer -

All depends on how much you use, and how quickly you can replace the charge. Best bet is to develop the information yourself. You can use the battery volt display as your guide, but for an accurate reading you can't be using the batteries at the time you make a reading (can't be charging or significant discharge). It takes a while after charging for the reading to settle down.

Fully charged - 12.65v
75 % charged - 12.45v
50% charged - 12.24v
25% charged - 12.06v
Fully Discharged - 11.89v

Don't run the batteries below 50% charge - it reduced their ability to take a charge. I know, I had to replace mine already 'cause I ran them too low too many times.

Our boats come standard with two house batteries - about 100 amp hours each. That means you can use 100 amphours before it is time to recharge (50% of 2 batteries each with 100 amphr). The fridge (in the Pacific Northwest) on my boat draws 3 amps when it runs, and is on for about 1/3 of the time. So it uses 24 ampshrs/day. So, if nothing else was on, I could run for 4 days before recharging. My experience is more like two days maximum with the stuff I use.

Both Capt D & I have added 260 watts of solar on our boats. It cost close to $2k. I added two additional house batteries as well. We have stayed on the hook for 9 days without running the engine or plugging in here (in the raining ole' Pacific Northwest) and had plenty of power. Only time we had trouble was when it rained hard for three days. Had to start the engine then....

Mac

 

[terraplane]

Thank you guys so much...this is better than going to school
I'll check the batteries as suggested. The meter at the help seems pretty non functional to me..barely moves .

All this info is very helpful. Thanks again

tom

 

[j&lgray]

Hi Tom,
The Laurie Ann's pattern is three or four days of cruising, 2 to 6 hours a day and then staying put for two to three days. Sometimes we plug into shore power and sometimes we anchor out. We anchor out 1/2 of the time. I watch the voltage levels on the batteries and particularly the #3 twin house batteries. In the pattern described, we have never had a power shortage issue, however, we do not have a TV/DVD combo or any big consumer of voltage. Between the engine charging and the shorepower use, our batteries have been fine, but we have set the conserve limit of stand alone battery use at 48 hours. We have looked at the solar option and decided it is not for us. If we upgrade our 12 volt system, it will adding house batteries that have more amp/hour capacity.

We have found our limiting capacity is not battery but fresh water. That is what makes us seek out land facilities. I am thinking of a water maker . . .

 

[Stella Maris]

Tom,
The solar panels are from West Marine. We do not use them to charge the batteries but to maintain them. Once we drop the hook, we set up the panels to just keep them topped off. It seems to work well as we run the refrigerator and the stereo all day long..... Got to keep the beer cold and the music going.....