how do you add a converter?

[turf]

i have a question.
i have a skoolie with a 12.5kw generator hanging from it. all of my 120v needs are covered. i want to install a 12v converter, so that i can charge my battery while parked and camping with the generator.

another forum advised me to install a battery bank, inverter, fusing, before i think about adding my rv loads. i do not want an inverter at this time. i do not wish to plug into shore power.

how do you know if the truck can handle the load?

to the vehicle's current load.... i wish to add:
12v lights
12v water pump
12v macerator pump
12v tv
12v rv furnace (in the future)

instead of installing a new battery bank and moving all my rv loads off the truck battery, whats wrong with just wiring my 80 amp converter/charger from the genny to the truck battery? that way i can recharge the truck / house battery when the genny is running.

now... my bus uses 2 group 31 batteries for a truck battery (220ah rated)
the gen uses a seperate grp 31 battery (110ah rated) for starting

the 1 gen start battery would be isolated to never drain.

that may not give my the reserve ah i was looking for originally......but it is the set up i commonly see on skoolies.net.

my predicted daily battery use is between 80- 120 ah per day..... normal is the low number, max is the high number.


currently the bus has a 12v fridge running on the truck battery. i currently recharge the battery with an auto 120v battery charger plugged into the outlet of my genny.



of that 80ah load..... the already running fridge is about 60ah (guestimate).

i want to run a hybrid system..... 120v large loads run when cooking, and small 12v loads the rest of the time.

thanks for your help

diagram for detailed explanation:
https://www.lucidcha...65-2b000a008615

http://www.lucidchart.com/invitations/a ... d40a009252


the items to the right of the dotted lines are what is to be added with calculated max loads

[cschlessman]

Well first off starting batteries dont like cycling. So you would need to get deep cycle batteries. Next most deep cycle bateries dont like to be discharged more then 20%, but you can find some that dont mind a 50% cycle and as long as you keep them watered and charged they are happy. A good bet is to have 2 times your max load in batteries this gives you a deeper reserve if needed. Last of all, it should be no problem doing what you want if sized properly. Im sure someone will disagree with me and thats okay thats what the fourm is for exchange of ideas. Have fun.

Chuck

[lornaschinske]

We went with the Intellipower 9200 Series converter/charger with Charge Wizard. The converter/charger is wired into one of the panel box breakers and then into the battery bank. Currently our battery bank consists of the single battery we originally bought to start the bus with and later used to run the 12vDC stuff in the food cart. All we run on 12vDC right now is the water pump. Later we will add more 12v stuff along with a couple dedicated inverters. When we do that, a larger battery bank with be put together consisting of 12vDC deep cycle marine batteries. We do not have the height needed to use golf cart batteries and I don't think they would function too well with an inch or so sliced off either the tops or bottoms of the batteries.

We do not boondock. We only need batteries while wallydocking for a few hours at a time or when the power goes out.

I'm sure someone will pipe up and say we wired it up wrong or that we can't possibly use 12vDC marine batteries as a bank. But the Class C used a single 12v Deep Cycle marine battery from Wal-Mart from 2006 thru 2012 when my daughter decided it was dead (bad wire) and replaced it. And it was running off a dumb 1980's era converter/charger.

Rule of thumb... add up your amp hours then double to find your required battery bank. Round up to find battery total amp hours. Better more than less. Bear in mind that you will never run ALL your 12vDC/inverter stuff at the same time.... IE you have 20 lights but you normally have 5 turned on at any given time... add up the amp hours of the 5 lights.

[gbstewart]

heres a link to a good place for converters
http://www.bestconverter.com/
gbstewart

[roach711]

Originally Posted by cschlessman

Well first off starting batteries dont like cycling. So you would need to get deep cycle batteries. Next most deep cycle bateries dont like to be discharged more then 20%, but you can find some that dont mind a 50% cycle and as long as you keep them watered and charged they are happy. A good bet is to have 2 times your max load in batteries this gives you a deeper reserve if needed. Last of all, it should be no problem doing what you want if sized properly. Im sure someone will disagree with me and thats okay thats what the fourm is for exchange of ideas. Have fun.

Chuck

Good info here. As said above, deep cycling your starting batteries will drastically shorten their lives which will eventually bite you in the butt, usually at the worst possible moment. Lorna's suggested converter is another good suggestion. The charge wizard does a good job properly charging your battery banks.

To install a converter you just wire the converter input to 120v wiring and wire the 12v output directly to the battery bank. If your starting and house banks are connected the converter will charge them both. A decent sized house bank will cut way down on your generator use and as a bonus you won't have to annoy the neighbors by running the genny in the evening to power your stuff. You can just run it mid-day to charge batteries or charge both banks from the bus alternator if you're doing much driving.