BATTERY HOOKUP

larglo · Post by **larglo** » Mon Sep 14, 2009 9:31 am

Hi all,

I have been looking into how I can hook up my battery system. I have had our F25 HT for about three months, and the batteries now are as such. Two batteries, one as the starting, which runs to a switch, as ONE, then a house battery which is connected to the switch as TWO.
I have added a new fridge and microwave and have an inverter hooked to the house battery. I'm not sure how long the one battery would run the fridge which runs 90 v and 1.3 amps (sign on back) the microwave would ony run for 60 to 90 seconds at most at a time.
So here is my question,,,,,,,, I want to isolate the starting battery, and use like a car battery system. Then get two batteries, hooked together to use to power the inverter, and operate the fridge and microwave while away from the slip for a day on the water.
First,,,,will the two battery/inverter operate the fridge and the little use of the microwave for a day in the water, then on returning to the slip and hooked to shore power, have the trickle charger recharge the two house batteries. Does this sound like a plan that will work?
Thanks for any feed back on this. I would like to get rid of the switch for various reasons.

Larry

g36 · Post by **g36** » Mon Sep 14, 2009 10:58 am

opening a big can of worms here as seen by other posts on battery setups on this forum. on my f32 i have installed 4 golf cart batteries as my house setup i also run an invertor for things. this came from my sailing days. we usually leave the dock friday afternoon and come back sunday late. i can operate this set up for several days without starting my generator to recharge, with any batteries you need to avoid deep discharging them as this shortens the life considerably. i believe that with only 1 12v deep cycle you will not be able to avoid discharging it probably in 1 day from the refrigerator useage not taking into account your lights, toilet if electric,fans, radio etc. i changed my anchor lights to leds depending on what bulbs you may have you would be suprised at how much this uses all night long. you need to consider the length of time you want to stay out and add up all your 12v needs and size it to fit. my setup with the golf cart batteries works great for us but may not be what you need. at the very least i would double up on your single battery house bank and i would make sure to keep your starting battery seperate. if only staying out during the day then probably the 2 battery set up would be fine. i take it you are running the refrige from the invertor. to do away with the switch also if you installed a battery isolator it would charge the house bank while underway. you could leave the switch for convience. you could just rewire it to add the house bank on if you ever had to start the boat from the house bank other wise leave it turned off.

randyp · Post by **randyp** » Mon Sep 14, 2009 11:30 am

Here's what I've done to the might Blue Heron (26' HT).

Original set up was like yours. 1 group 24 battery for engine, 1 group 24 for house. One "1-2-all-off" battery switch. The whole set up was installed in the stairwell going into the cabin and the switch was on the outside of the top stair riser.

I have the following set up that allows me to stay for 1-2 nights at anchor (no electrical AC hookup) while running the Norcold AC/DC fridge, lights, stereo, etc.:

1 group 29 battery installed in original battery housing under the top stair into the cabin. 2 group 29 deep cycle batteries hooked together in parallel (pos to pos, neg to neg) - yielding approx 250 amp hours of juice to a house system that would max out at 25 amp hours if everything was left running. Actual useage is much less since I don't leave everything running and the fridge cycles its 8 amp DC load about 15-20 minutes per hour not running continuously.

The whole system is hooked up to a Blue Seas Auto Charging Relay (ACR) switch that automatically senses the amps and volts from the starting (engine) battery and the two house batteries. It will NOT allow the engine battery to get combined into the house bank so I never, ever can run the enging battery down by mistake. It automatically charges both battery set ups while under power (off the alternator) or plugged in (off the 20 amp battery charger). I also installed a new battery switch (1-2-all-off) instead of a dedicated switch for each battery, due to space constraints.

I leave the battery switch on "2" (House Bank) all the time, because the Blue Seas ACR make the whole system foolproof.

I run a small 600 watt inverter for an AC fan and to charge my laptop.

I think your inverter will suck the current battery dry in short order, and I would not use a large inverter anyway due to battery drain. If you have a Norcold fridge on the boat it's set up to run off battery power when not plugged into an AC source and will run off AC when it is plugged in. This will save your batteries, or you can turn it off when under power.

You can increase your battery capacity by going to larger, deep cycle 12 volt batteries for house load, or 2 6-volt golf cart batteries wired in series (pos-neg, pos-neg). Either way go with a good deep cycle set up for your house bank - one that will take repeated charge-discharge. For cost, I use trusy Walmart MAXX-29 batteries and replace them every 4 years. I'm on my second set and they have stood up well. I use 1 for the engine/starting battery, and 2 in series for the house bank.

Finally, if you're planning extended overnights off the dock, think about investing in a small portable generator. I bought a Honda 2000 EU a few years back and use it on the boat and have used it as a backup at home during power failures. It's a great unit - pricey, but won't let you down, and very quiet.

Hope all that helps.

larglo · Post by **larglo** » Tue Sep 15, 2009 8:56 am

Thanks to both for your ideas, they helped and I copied both posts to sve in my notebook for our boat.

I do not have the 110/12v type of fridge. But it is small enough to just fit in the space provided.
My inverter is a Cobra 1500 watt model. The only thing I will power when away from the slip will be the fridge and the microwave, two, three times a day. We will be out only during the day and return to the slip each evening before dark to sleep.

I am happy to hear a two battery system will most likely keep up with the power I'll be using for one day's use. I will also check out the Wally World (Wal-Mart) battery.

Thanks very much again.

Larry

randyp · Post by **randyp** » Tue Sep 15, 2009 9:06 am

By the way, I did not tell you where I put the house bank (2 wally world batteries). They are in the area under the portside seat in the cabin. There is a storage space there and I removed some of the lead ballast that was foamed in place, then cut a piece of 3/4" plywood for a floor over the remaining ballast on which to mount 2 battery boxes for the group 29's. I removed some of the ballast to compensate for the weight of the batteries going in that area. From there I ran the wires (2 awg cables) from the house bank through the hanging locker and onto to al common ground (engine block) and ACR and battery switch.

Not sure if the F-25 has the same interior set up or not. You could mount your larger house bank of either 2 6V golf cart batteries, 2 group 29s (like mine) or just about any larger battery like a 4 or 6 in the engine compartment if you have the room.

There was a good post here a few years back about the Wally World set up I am using, and there are tons of good tech advice on the web as well as many manufacturer's sites. I found the Blue Seas site and tech advice to be very helpful.

captain don · Post by **captain don** » Tue Sep 15, 2009 10:22 am

Set up the system like you want and stay at the dock one week end without shore power. Captain Don

jddens · Post by **jddens** » Tue Sep 15, 2009 8:04 pm

My system is much like G36's. 4-6volt golf cart batts for house power and 1 large, cranking batt, and 2 perko switches. Both systems are separate but combinable. I have a 2KW heart inverter and run a small 110V refer and occasional micro wave and a 16inch LCD flat panel TV with the usual lights, fan etc. I also have an electro-san toilet and that draws a ton of amps when cycling. I can do 2 nights and 3 days without issue, any longer and I run the starboard engine (no generator). I have a 120 amp altenator on the starboard engine specifically to charge the house batts.......sounds like you should be good for a day with the setup you discussed.................I fully agree with capt'n Don.....stay in the berth with shore power disconneted for a couple days and you will know exactly what to expect......John

mpulsev10 · Post by **mpulsev10** » Tue Sep 15, 2009 8:34 pm

Do you guys have any diagrams of your set ups?

thanks.

foofer b · Post by **foofer b** » Tue Sep 15, 2009 9:00 pm

A large "5 day" cooler from Walmart is a cheaper and simpler solution. I freeze blocks of ice in small plastic trash cans (Walmart again!) in our chest freezer and can keep the food and beverages cold for 3-4 days. Then we use the fridge mainly as a pantry.

foofer b · Post by **foofer b** » Tue Sep 15, 2009 9:04 pm

Oh, and the Honda 2000 can be had for $869 delivered form Wise Sales.

jddens · Post by **jddens** » Tue Sep 15, 2009 10:14 pm

I still bring an ice chest for drinks...all the opening and closing is hard on the refer. My boat is 15 minutes away and I'm down there several times a week if not everyday. It's nice to have cold beverages and food on board without dragging an ice chest every time....when we overnight I pre-freeze what ever I can and that helps to.......love having the refer day to day.

foofer b · Post by **foofer b** » Wed Sep 16, 2009 5:38 am

Well sure, if your plugged in at the dock, why not. But when on the hook, the fridge can run down the battery quickly, and block ice lasts way longer than cubed or crushed.

g36 · Post by **g36** » Wed Sep 16, 2009 7:17 am

no coolers for me. i dont need anything else to have to load up and bring to the boat. lots of my buddies use coolers but i'd rather not. i actually make my own ice with a counter top ice machine that makes more ice than we need once it gets started. i even on some weekends run a second refrigerator while out. i have a battery setup that does perfect for us. i do not suggest i have the best or most preferred set up but its perfect for me. i can stay out easily for the weekend and have gone almost 4 days with out having to run my generator to recharge. yes the refer does draw alot of amps over time but if the house bank is right it wont drain them that quick. of course i also have friends that turn their generator on when they leave the dock and never shut it down till they are back. thats for them not me, i like the peace and quiet. we do usually run the generator 30 minutes in the morning for coffee and to heat up the water heater. one of the biggest things to check is make sure the door seal on the refer is sealing and you are not loosing all of your cold through a leak, also make sure it has the ventilation to get the heat away from the coils there is certainly arguments for carrying coolers but its just not for me.
if you want to easily know how much you drawing from your batteries find a current clamp and put it on your batteries and turn on your dc loads and make a note of the amps you can then figure your current draw and properly size the house bank

jddens · Post by **jddens** » Wed Sep 16, 2009 11:12 am

footer..............point is if the refer is stocked at the dock and i go out for a few days it is still stocked and needs to run while on the hook. And my batts and inverter do that real good..............John

foofer b · Post by **foofer b** » Wed Sep 16, 2009 7:59 pm

Thanks for the info, I thought I would surely drain my house bank-2 deep cycle batteries. How much is a current clamp?