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Building a job trailer. Cheap AC/DC inverter ideas? Other thoughts?

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fastline

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I am getting ready to build a building in a remote area. Because I already have a couple semi trailers, the idea came to me to simply setup a trailer to keep everything I need in it and make a sort of mobile work shop. Nothing fancy or elaborate as this is most certainly temporary. However, I few things came up that would really help me out and would really like to run an inverter setup for some of this if possible.

Some of my stuff will certainly require a generator to run, and I understand that, but I really need to plug in simple small battery chargers over night. And rather not drag them home. I have a Honda EU3000 inverter generator, a 6500W standard genny, compressor, lights, etc. The Honda is a real sweetheart because it can automatically idle down and conserve fuel when under light loads. However, even at idle, it will drink way too much fuel running 24/7. I think it is smarter to charge up batteries with it, and bank some power when it runs?

Here is a quick list of things that I would like to have.

1. Refrigerator. A real one, with a compressor, not peltier. Really the only need is to help keep sandwiches and such cold. I know from experience these don't pull much power, but starting the compressor could be tough.
2. Fluorescent lights. I don't expect these to really all run on an inverter. Running on the Honda will be fine.
3. Charging small batteries - This is mostly what I need the inverter for. I have 2 way radios, and a couple small 12V batteries to charge over might. Obviously I could just take these home but nice to leave on the job, and just less stuff to have to drag back and forth.
4. A few other small loads.

I think the goal here would be cheap to free. I figure I have enough batteries and such around, I might be able to make this work, but mostly worried about the starting loads on the fridge? That might be a no-go? Also, if I use an 12v inverter, I do have a couple around for a car that I can rig up, but was not sure if they have much constant loss? Would a grid type inverter be any different with reduced losses?
 

tcmtech

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I think the goal here would be cheap to free. I figure I have enough batteries and such around, I might be able to make this work, but mostly worried about the starting loads on the fridge? That might be a no-go? Also, if I use an 12v inverter, I do have a couple around for a car that I can rig up, but was not sure if they have much constant loss? Would a grid type inverter be any different with reduced losses?
Figure Out your combined peak combined wattages then multiply that by at least three. Then multiply that number by total anticipated running hours between battery recharges and that will give your minimal realistic inverter capacity plus related battery amp hour rating you will need.

Realistically from personal experience with such systems and loads you list would be surprised if you can get by with anything less than a 2000 watt continuous rated inverter running off of anything less than three 100+ AH group 31 deep cycle batteries for just one days typical usage.

Also after all that you have to figure out what sort of power source you will need to have to be able to recharge said battery bank in a reasonable timeframe while all that load is still on which to be honest will likely require a 12 volt multi hundred amp source capable of running at that load for 4 - 6+ hours at a time.

Basically cheap and simple won't be in the design.
 

MikeMl

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Most Helpful Member
How about hacking the fridge thermostat to start the EU3000 when the fridge needs cooling or when the inverter input battery needs a top up?
Adding some solar panels for charging the inverter battery will help. This way, the inverter/battery could be much smaller if it never has to run the fridge.
 
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