Batteries and Power

[Andy]

Just curious what other sailors out there use for power. I have a new 33 with a start and house battery, but worry that it could be underpowered.I do not have a/c, but do have a refrig that is a big draw.We are week-enders now, no matter how much we wish we could be out for longer - still have to work and pay bills Thanks

 

[Terry Cox]

Andy, do you have volt meter? When the house...

gets to 11.5 volts it is time to recharge. Some will say that the battery is dead at 11.5, but there is still some power left, but not much. Running your engine for about two hours should bring the house up to last for awhile. How many amp hours in your house and what does your reefer draw? That will give you a guage as to when it is time recharge.Terry

 

[Bill18593]

Why wait that long?

Hook up the charger whenever possible to top off the batteries. My understanding is that its better for the batteries to keep them near the top of their potential.

 

[nick8481]

Increase House

Add A secound house battery and seaperate the start battery from the 1-2 switch and add a WM combiner.Thats what I did and never get stuck out on a weekender,I also have 12volt refg and lots of electronics. Nick

 

[Gregg18047]

Andy -

Have the same boat, no A/C, no radar (yet), and probably a lot of the same options as you. The fridge alone draws almost 6 amps when running. Running lights draw almost 2 amps, same for the anchor light. It adds up quick.I currently have 2 group 27 deep cycles at 90 aH each (not enough). I'm adding a seperate starting battery this week and paralleling the 2 deep cycles for now. When they go, it's golf cart batteries for the house and some kind of solar panel.A good thing to do is figure power consumption in amps for every electrical item on the boat, figure the amount of time you use each item in one day, and add it all up for your daily consumption. Then triple that amount to figure how much capacity you should have in a house battery.I highly recommend Don Casey's book 'Sailboat Electrics Simplified', available here in the chandlery.

 

[MichaelStacy]

Extra Batteries for H33

Andy,I also have the H33. I just added two golf cart batteries (got from Sams club), and now have four batteries in 3 banks. Bank 1 is the two golf cart batteries, bank 2 is one of the original group 27 batteries, and bank 3 is the other group 27. The H33 has a three (independant) output battery charger. So, I wired an output to each of the three banks. I added a couple of extra switches (and a combiner from BEP marine). One switch connects the house battery, the 2nd switch connects the start battery, and the 3rd switch will parallel the 'extra' battery (bank 3) across the house batery when I am using the house bank for the weekend. There is a 4th switch which is the 'emergency' parallel, for when you need to parallel the house to the start bank for starting, which I hope I don't get into the situation that I resort to this.All four batteries fit in the battery compartment.All of the above required re-wiring the main 12vdc panel lead to the house battery, the start lead to the start switch, and the windlass power to the start battery. (there seems to be several schools of thought about where to connect the windlass)While I was at it, I also added a 1500W inverter (from Costco), a relay so that shore power and inverter don't mix...

 

[Fred Ficarra]

Or

you can do it this way. Simple. No nothin' to do. One bank. No engine start battery. This is it. (did I say that?) All you need, is to know what you're doing. Buy the book. Oh, charging and shore power change-over is handled by the Prosine inverter with a 100 amp 3 stage charger built in.

 

[Bill18593]

Fred,

Are those 6V golf cart batteries?

 

[Patrick]

Get golfcarts

I have a 33.5 Hunter.Had it two months, took out the one house battery and put in 4 golf carts.Works just dandy.

 

[Fred Ficarra]

Bill, yep.

 

[Terry Cox]

While we're on the topic of batteries...

the cell plates in one of our 8d's were exposed to air for a period of time, maybe weeks. I topped off the batteries, but I suspect the damage has already been done. Once exposed to air are they toast?Bud

 

[Buck2796]

One More Thought .....

Although I have a 420 w/ AGM's ... I carry a separate, spare, Group 27 battery that I keep (totally disconnected) in a locker. No matter how careful you are, one day, you are going to get up and your batteries (including your engine start battery) are going to be too dead to start the engine. It will happen !!!With another battery and a pair of jumper cables, you're good to go.(I put a battery charger on the spare battery every few months to make sure its charged).Maybe I'm anal... but wait till it happens to you and you'll carry a spare battery, too.

 

[Fred Ficarra]

Buck, maybe, but there is a little known resource

in Yanmars. If the dreaded unavoidable day ever happens and the engine won't crank fast enough to start, then stop cranking immediately. Open all compression releases. Then spin up the engine. It won't have a load on it so 4 golf-carts will have no trouble even when DEAD. (voltage in the low 11's) Then close one release. The engine will start, assuming you don't have another coincidental defect like air in the fuel. For most boats this is a two person job. One to push the start button and one to activate a cylinder lever when up to speed. For that reason I have an axillary start button on the engine box. And I've never had to use this method. The engine always starts no matter how low my batteries. One more thing, the compression release levers in the Yanmar manual are referred to as the 'low battery lever(s)'. The start button is seen at the upper-left of the picture. There are two buttons. The other is for a second solenoid shut-off.

 

[Buck Harrison]

Thanks Fred,

Never knew my 4JH2 had compression releases. I learn something new every day... I'll ck it out.But,I have had one or two instances when my batteries were too low to turn the engine over.Guess I'm just paranoid.... What is "second selonoid shutoff" .. what isthe purpose of the second selonoid???

 

[Fred Ficarra]

Buck, that should read 'second shut off' station

or 'engine kill location'. I use a solenoid shutoff in place of the push-pull cable. The other push button is to activate the solenoid to kill the engine without having to go topsides. Here's the solenoid.

 

[Fred Ficarra]

Bud, having your plates exposed will shorten the

life of the battery but it's not a killer. Just keep 'em covered from now on and you probably won't notice the difference. Besides, what do you need batteries for down in Willapa Bay? You can't get out past the crashing waves can you? Just stay in port on shorepower.

 

[DonaldDo]

One Battery Bank

Fred,Impressive bank of golf cart batteries. Although simple with one bank, you risk not being able to start if someone 'left the light on'. Based on your picture, you have hooked all the batteries in one series-parallel bank of 12V.I would warn others who wish to set up their batteries to follow the basic methodology of the other post (reply #5). He at least has the house and start batteries totally independant. Similiar to the technical advisor article in the West Marine catalogue.The problem of one bank of batteries permanently wired in parallel is that one weak battery will work on the others, over time. And, if one cell of one battery goes bad, it'll drag the others down. With them seperate, you can live with someone "leaving the light on', because the start battery is independant and will still be ready to start the boat (so you can charge the dead house bank...)Don

 

[Dipboye]

Non marine inverter

Question for MichaelStacy:I saw the 1500 W inverter from Costco. I'm struggling with my instinct to only go with marine grade electrical sysstems vs. my cheapness -- the unit was only about $90. Where did you get the relay you describe that switches from shore power to inverter power? Also, why do you have memberships at both Costco and Sams club?

 

[Fred Ficarra]

Thanks Don, good advice.

But factor in these points;1.I've been running setups similar to this one since about the time the West Marine adviser said to do it my way. There was no such thing as combiners in those days. And if you think this bank is impressive, I've run six golf carts in this location.2.This setup is not about to die because of a left-on light. One time I practically used the starter motor to go from Costa Rica to the Panama Canal. Why my starter didn't turn to molten slag only attests to the quality of the product.3.Maybe it won't start someday but read reply #11.4. Look closer at the picture of the battery bank. There is a device laying next to the batteries with a black bulb attached to a clear glass tube. It's called a hydrometer. It is used to measure specific gravity in each cell so as to know when equalization is required. It is THE tool to also identify a failing cell. Again, like I said in reply #6, buy the book and know what you are doing. But then too, anyone day sailing out of a marina probably doesn't need to go to the trouble of the learning curve. I took this setup cruising for 10 years in the tropics and never bothered to learn some things like celestial navigation. I was too busy installing 'stuff' on my boat like GPS.5. Most of this philosophy is on my web site.

 

[Fred Ficarra]

Dipboye, I don't know why you couldn't do it that

way. I run a transfer switch on my camper for the generator/land power change over. The original failed and the replacement was $60.00. It came in a box from a web site with no instructions. Typing in the name of the product yielded their web site and the instructions for installation were located 'front and center'. The web even saves printing costs. But the key word is 'failed'. The first camper switch died after 5 years. And it was almost unused. Checkout the life-cycles that a built-in switch from a Xantrex Prosine inverter is engineered for. Seems it's over 300,000.And don't go by the price in the WM catalog. Shop around. I bought my Prosine 2.0 from these folks. http://www.vitmarine.com/index.htmlSay hi to Everett for me.