12v battery bank + 3000w inverter

[darksheep85]

Hey yall, I just wanted to put my plan out there for criticism, either constructive or destructive.

I have a plan to install a 12v alternator with the kit I'm getting from tm america. It will be used to charge a small battery bank of probably 4 large batteries in a battery box I will build and attach to the frame where my unused spare tire carrier is. These batteries will be wired in parallel for 12v and maximum amperage. Then, wired to a 3,000/6,000 watt inverter that I already have. This inverter will be placed in the bed for powering "camping" equipment.

The batteries will also provide a source for 12v accessories, such as lights, radio, cb, transfer pump, gauges, etc.

The idea seems perfect and almost complete in my head. I'm at the "gathering parts and preparing to execute" stage of this endeavor. What I would like is info from anybody who's done something similar.

What are the pros/cons of the different types of alternators I can use (10si, 12si, cs130) and what would be the best way to wire them? The 10si and 12si seem pretty straight forward as far as a 1 wire hookup, but the cs130 looks a little more complicated.

Is the battery box location I proposed a good idea, or would it be OK to bring the batteries into the bed, as this would be the so-called "living quarters"?

What kind of batteries would be best and most economical choice? Marine? Deep cycle? 18 wheeler style batteries? They will probably be drained dead every once in a while.

What size wire should I consider using throughout? Are there more necessary components I'm not thinking about?
Such as relays, solenoids, fuses, circuit breakers?

The ultimate goal is to have a self sufficiency truck where I can have shelter, usable electricity, mobility. Future plans include finding a place to mount a water tank, and adding a 30gal stainless marine fuel cell I got for $20.

This is definitely a situation of "champagne dreams on a beer budget". But I am a patient man.

Any and all info or critiques will be appreciated.

 

[pjwest03]

In no particular order here...

A 3000 watt inverter will draw pretty close to 300 amps at full load. 2/0 cable close to the batteries and a 500 amp fuse if the inverter is within about 10 feet.

10si/12si/cs130 would be pretty undersized for the application. Something more in the 150-200 amp range. Drawing the batteries down will take a pretty stout alternator to charge them in a reasonable time frame. 2/0 wire and possibly 4/0 wire to reach your battery box location. The alternator line should also be fused. This was not commonly done in the past but the fuse protects the wire from shorts and starting fires.

Other than that, a 12v fuse/distribution panel and one for 120v. Wire sizes here are completely dependent on the loads and the length.

Only a deep cycle battery will survive that kind of discharge. 6v golf cart batteries are a popular choice. A battery cutoff switch is not a bad idea. I would keep the batteries out of the living quarters myself.

 

[Recovry4x4]

Consider a Leece Neville 110-555JHO. Rating is about 160A, they are widely used on over the road trucks and easily obtainable. Many Freightliner dealerships have a 24hr parts dept.

 

[rustystud]

In no particular order here...

A 3000 watt inverter will draw pretty close to 300 amps at full load. 2/0 cable close to the batteries and a 500 amp fuse if the inverter is within about 10 feet.

10si/12si/cs130 would be pretty undersized for the application. Something more in the 150-200 amp range. Drawing the batteries down will take a pretty stout alternator to charge them in a reasonable time frame. 2/0 wire and possibly 4/0 wire to reach your battery box location. The alternator line should also be fused. This was not commonly done in the past but the fuse protects the wire from shorts and starting fires.

Other than that, a 12v fuse/distribution panel and one for 120v. Wire sizes here are completely dependent on the loads and the length.

Only a deep cycle battery will survive that kind of discharge. 6v golf cart batteries are a popular choice. A battery cutoff switch is not a bad idea. I would keep the batteries out of the living quarters myself.

Good advice ! I would go with the 4-0 welding cable myself. Make sure all the batteries are the same ! This is important in a system like this.

 

[darksheep85]

All good advice. Thanks. I have been seeing some 12si alternators for sale online with 200 amp output. Just have to get one with a V-pulley. There are specialty alternators out there that have upwards of 400 amps made for emergency equipment and rolling stereos, but the prices are ridiculously high.

 

[Nomadic]

Some things to consider is temperature and plan how long you expect the batteries to last before they die and spend accordingly.


I live out in the country and use a laptop for work. If my inverter goes out, its as devastating as a broken stove.


In the winter, its been as cold as 9F and I get about 5 minutes runtime off one deep cycle battery. In contrast, at 70F that same battery will give me 45 minutes to 1 hour. When its cold its a waste of time and I just leave the vehicle powered on (its a Volt) and run off the reducer (alternator component). Ideally I'd have a warmer for the batteries.


Look at the operating temperature range of your inverter. My inverter needs to be warmed up in the AM before I turn it on below like 40F, otherwise the fan complains and it probably does that because I didn't follow the destructions in previous winters (too cold to run).


About battery longevity, consider how many times you want to discharge the battery in a 24hr period, to what voltage will you draw down the batteries to before recharging and how long that time period is (from charge to recharge time). Going down lower than 12.4v can cause sulfating in a deep cycle starting battery.


Consider a battery monitor to alert you when its time to recharge so you can get more life out of the batteries. I'm using a Radio Shack USB multimeter and a custom program I built for Win7. When voltage gets low, the laptop speaks and reminds me to power the car on which recharges the battery via jumper cables. Then it says when its float charging and that is when I power off the charger/car and disconnect the jumper cables.


Spend on some quality batteries, not the automotive/boat deep cycles and don't spend on Optima. I bought a new O'Reilly battery that had a born on date the same month I purchased it. It lasted 2 months and failed to hold a charge. I got a new one with their killer return policy, but lesson learned. This short life was because I recharged it probably 6+ times a day and drew down to 12.1v. Look to solar power companies for batteries. Consider the Tesla battery (1,000 cycle count), or Trojan brand or some other purpose built battery for solar, forklifts, etc. Buy sealed so you can have them inside and keep them warm.