Im planning on running a power source to my toolbox and mounting a power inverter inside so i can have a power point in the bed for things like charging drill batteries and running lights and other items when im out. my question is what kind of continuous wattage do i need to be sufficient to run most items that may be needed. things like drill batteries, halogen work lights etc. im thinking probably 800 watts continuous power.

anyone with some imput on this is greatly appreciated.

 

Well, let's see what we can suggest. If you want to run 800 watts at 120 volts you will need 800 watts at 12 volts which will really be about 13 volts. That's 800 divided by 13 = 61.5 amps of current. No power converter is 100% efficient so you will need to allow for about 80% efficiency. We need to add about 10 amps for a fudge factor. From your battery to the tool box in the bed will require about 15 or so feet of cable. You will be needing at least 4 gauge wires from the battery to the tool box. 2 gauge would be better. I would recommend reading the AMP section of this forum since your requirements are very similar to what the booming music crowd needs. It's very do-able, just think big wires and big fuses. You can run the wires in some form of protective sleeve under the truck. Have fun and hope this helps.

 

Actually, it takes closer to 1600W to fuel an inverter that puts out 800W. As a rough estimate, always figure 50% of the input energy is lost, so that means the input is double the output. But just look at the data plate or specs page of the inverter you buy to know for sure what it pulls at peak load. Then install a dedicated fuse holder near the battery with a slightly larger fuse. Mine pulls ~128A (~65% efficient), and I had this 175A fuse & holder in my junkpile. One day, I might change it to a 130 or 150.

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I have a similar inverter for my Bronco, but it just has jumper-cable-style clamps so it's portable.

As to the size of inverter you need... That's up to you. Consider the MOST stuff you'd ever want to run at one time (maybe a light & a heavy tool) and add their specs. If they're given in W, simply add. If they're given in Amps, multiply by the specified voltage (110-125) to get an approximation of Watts. Once you have the total peak Watt load, start shopping for inverters.

You can install 3 inverters, each to run 1 of 3 heavy loads, but you can't combine inverters to supply one load. I'd install 1 fuse per inverter.