wiring inverter to 2nd battery

[wkbrdngsnw]

I'm thinking of getting a 2000-2500 watt inverter for the back of my 1009 to power some tools and a small compressor. Since the 24v ones are more expensive my budget limits me to a regular 12v one. I already have my winch being powered off the front bat and its also powering the inside of the truck with all my extras. So I thought that the second bat would be a good place to get power. I still have the radio power wires to the back and I could move the wire that goes to the ground bus under the hood could be moved to the negative of the 2nd bat and be at 12v and the hot would be 24v. My electrical theory is a little rusty but that seems like it would give 12v with 12v elevated ground. Which shouldn't matter as long as its isolated from ground. also, bigger inverters have a ground terminal and neutral so where would I ground that? If it went to the frame it would be 24V from the positive and it probably wouldn't like being attached to the neutral. Or should I just put it on the front battery and rotate them occasionally and not worry about it?

 

[lavarok]

Use the rear battery NEG terminal which is where the 12v bus in the truck derives its power.
The rear battery NEG term is tied to the front battery POS term, so it does give you the 12V you need.

On a side note, does any one know the exact reason they tap the 12v at this point and not the front battery POS terminal? I have some thoughts on this myself, but they are unconfirmed ideas. I'd rather not start some rumors!

 

[JAsher45]

IMO i would still run it off the front battery. I would just run a new cable to the rear buss bar. have all 3 terminals ground, +12, +24 . even though you have your winch tied into the front battery, odds are you are not going to be opperating both the winch and the inverter at the same time. just be simpler and may save from any of those electrical gremlins from popping up.

 

[Stalwart]

NOOOOOOOOOOOOO, if the inverters case is grounded, do not use the other battery.

 

[lavarok]

I should have read the first post more carefully.
If you want to use the rear bus bars, move the RED to the rear battery NEG ( 12V+ ) and leave the BLACK on the ground bus bar.

That will give you 12v, just like the truck uses for the lights, etc.

 

[mistaken1]

If you use the rear battery you will need to isolate the inverter case from the vehicle. You can connect all of your ground/neutral points to the negative side of the back battery.

When you do this (assuming you isolate the inverter case from the vehicle chassis ... read mount it on insulators) you will have 12V between the inverter case and chassis of the vehicle.

Now when you drop a piece of metal on the inverter case and it finds bare metal on the truck chassis that piece of metal will weld itself to both contact points (or blow itself clear).

If you get between the inverter case and the chassis your body will conduct current (how much depends on the resistance of your skin which gets quite low when wet). It only takes milliamps of current across the heart to kill.......

 

[wkbrdngsnw]

I thought about it a little more today and the second battery idea may not be worth the risk of burning up what to me is an expensive piece of equipment. I like the idea of moving the wire from the 24V bus to the negative of the 2nd bat since the positive of the first already has the winch connections. Also if I leave it on with the truck off and run the battery down I would have a hard time trying to convince somebody to jump my second battery.

 

[hovenga67]

Just mount it like you do an amp for a stereo. Get a piece of plywood to mount it on. Make a cover with breather holes and you do not have to worry about it grounding out. You only need this if the case is grounded on the inverter. I have debating on doing this on my winch. With my fans and other stuff running it is pulling real hard off the front alternator. Another option is to have your alternator rebuilt to put out more amps.
Brent

 

[notsosanestan]

i got this inverter DCACPOWERINVERTERS.COM - 24V DC to AC 900 Watt Power Inverter and am wiring in to the 24 buss behind the passenger seat

 

[Screamin' Metal]

Heres what I did, mounted my 3500 watt inverter to the rear bulkhead of the cab on a fiberglass panel, attached it to a big 12 v. battery in a pastic battery case, that being in turn wired into the 12v.tap on the firewall by the brake booster. In that line I also put a battery isolator, so, if I'm sitting there with the engine off and the lights on working, I won't run down my starting batteries, but will still charge the extra battery when the motors running. Also....if one of the starting batteries for the 24v sections lay down, you can either charge the batteries or jump from the extra.

I run alot of tools off my inverter, I run a small compressor for airing up tires and blowing air, cleaning stuff.....also alot of electric impact use, lights, that sorta stuff....

After 3 years.....no problems.....and that extra battery to jump from helps tremendously......
Just an idea.........

 

[Screamin' Metal]

OR.....just do the 24 v inverter......and wire it into you buss bars.......but they do suck down some power if your putting a load on them and they do put out alot of heat. Mine has 6 fans on it and gets plenty warm.....but I wouldn't go without one......
You can even get them in the 240v versions.....but thats really serious territory there......I've wired a few of these up in the Dueces......but thats classified.......