Inverter needs-how much

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I recently purchased a 100w Harbor freight solar kit. It has everything except an inverter and batteries. I also purchased two 135 anp. hr., marine batteries. I have no idea what size inverter I should buy to complete the system. My understanding is that I should find out what the largest surge wattage use is, for the equipment I will use , then match that wattage. Can anyone give me a simple answer. Converters are expensive and I'm thinking along the lines of 750 watts continuous, 1500 watt peak modified sine wave inverter. Helpppppp
 
Without knowing what you will be running, e.g. running computer, charging phone, refrigerator etc I’d say what ever wattage you get a sine wave inverter is the recommended kind to get for the most part. Again just depends what you will be running. There is quite a few YouTube videos on calculating what you might need.

I too have a 100w solar kit and use a 1000w sine inverter made by Wagan.
 
As RoarinRow said. You really need to post up what you are trying to run. Keep in mind that if you have dreams of running a Pressure Cooker, (not me but it has been tried) it ain't gonna happen. Too much power draw.

If you just want to charge laptops and other low power draw items which can't be charged via a USB port then a 1000 watt will probably work. My recommendation would be to not go cheap and make sure you get one that goes direct to the battery vs one that plugs into a 12 volt socket.

Search here and the Expedition Portal forums. This topic comes up regularly with lots of good info provided.
 
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Minimum 1500 watts if you want to run any type of kitchen appliance or a drill etc , you can get by with 400 if your just charging ancillary items like phone or a laptop. I have that same harbor freight solar system and have found its much better to leave at home and use as a trickle charger to keep batteries charged, if your gonna use like youve described get deep cycle batteries with 400amp or more capacity. The inverter will drain the batteries quick once sun is gone
 
750W continuous isn't enough for, for example, most hair dryers and waterboilers.
I totally agree with RoarinRow that it depends on what you will be running. Also I suggest that to preview some watts in reserve.
 
I need to charge 24V batteries so a pure sine wave was needed. A small 600 watt unit was simple to wire off the main battery, has a small foot print. It well not run a coffee maker.
 
Without knowing what you will be running, e.g. running computer, charging phone, refrigerator etc I’d say what ever wattage you get a sine wave inverter is the recommended kind to get for the most part. Again just depends what you will be running. There is quite a few YouTube videos on calculating what you might need.

I too have a 100w solar kit and use a 1000w sine inverter made by Wagan.
So what do you run in the way of equipment ? I have a lap top, I have a13' Scamp trailer that has a small water pump (seldom used), a few lights, uses 12v for refer on the road but propane when camped. I may use the TV in some cases but doubtful it will be used for dispersed camping which will be most of the time. I would like to use a small microwave and toasting oven (not at the same time) if the inverter can handle that. I've watched almost every YouTube video made and I have yet to see one that states what the lowest wattage inverter I can buy that will work for the few things I need power for. I have the small home made a/c unit I made from a 12v-80w fan, old cooler and I use hot ice in lieu of regular ice. The places I go the a/c is not usually an issue for camping at the altitudes I usually go. I will be buying a fantastic fan for ventilation when needed which should be easily handled by the battery bank. I'm told that the larger inverters use a fair amount of wattage so using the smallest would be to my advantage if my usage is low. Thanks for your input, all is helpful.
 
Another bit of info most inverters have a 12v ciggarette plug and gator clips to attach to battery. the 12v plug will only allow the inverter to work at 1/4 capacity the direct battery connection lets it use full power

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So what do you run in the way of equipment ? I have a lap top, I have a13' Scamp trailer that has a small water pump (seldom used), a few lights, uses 12v for refer on the road but propane when camped. I may use the TV in some cases but doubtful it will be used for dispersed camping which will be most of the time. I would like to use a small microwave and toasting oven (not at the same time) if the inverter can handle that. I've watched almost every YouTube video made and I have yet to see one that states what the lowest wattage inverter I can buy that will work for the few things I need power for. I have the small home made a/c unit I made from a 12v-80w fan, old cooler and I use hot ice in lieu of regular ice. The places I go the a/c is not usually an issue for camping at the altitudes I usually go. I will be buying a fantastic fan for ventilation when needed which should be easily handled by the battery bank. I'm told that the larger inverters use a fair amount of wattage so using the smallest would be to my advantage if my usage is low. Thanks for your input, all is helpful.

Right now my 100w solar setup with 1000w inverter is mostly for running my laptop and charging multiple small devices, phone, bluetooth speaker, Apple Watch, 12v lights, etc. Then when I'm with the kids, then it's charging gaming systems, Smart TV, DVD, additional phones, tablets, etc. Then when it will be in camping mode, then coffee maker, air pump, and then down the line a refrig. My 100amp solar battery is independent of the main battery (for now) and only gets charged from the solar panel. Since this is my first solar setup, it's more of an experiment. If it turns out I need more power, then I'll upgrade.
 
Right now my 100w solar setup with 1000w inverter is mostly for running my laptop and charging multiple small devices, phone, bluetooth speaker, Apple Watch, 12v lights, etc. Then when I'm with the kids, then it's charging gaming systems, Smart TV, DVD, additional phones, tablets, etc. Then when it will be in camping mode, then coffee maker, air pump, and then down the line a refrig. My 100amp solar battery is independent of the main battery (for now) and only gets charged from the solar panel. Since this is my first solar setup, it's more of an experiment. If it turns out I need more power, then I'll upgrade.
This is the inverter I plan to buy. My 2 batteries are not connected to the car so the solar will connect directly to the batteries I'm guessing. I'm even more confused by some of the answers I am getting. Here is the converter and a video supplied by Harbor freight.
 
You will have to use a solar charge controller for charging the batteries. I am using the ones from Victron Energy in 2 rigs.
And still it depends on what you plan it to use for.
If it was my post that confused you please forgive me ;). My english lessons were a long time ago.
 
It is maybe a silly question (in this thread) but whats the meaning of RV?
 
This is the inverter I plan to buy. My 2 batteries are not connected to the car so the solar will connect directly to the batteries I'm guessing. I'm even more confused by some of the answers I am getting. Here is the converter and a video supplied by Harbor freight.
For a microwave and toasting oven as you mentioned, I believe that would justify the extra expense of getting a pure sine wave inverter compared to a modified sine inverter, but I am no electrician.
 
Right now my 100w solar setup with 1000w inverter is mostly for running my laptop and charging multiple small devices, phone, bluetooth speaker, Apple Watch, 12v lights, etc. Then when I'm with the kids, then it's charging gaming systems, Smart TV, DVD, additional phones, tablets, etc. Then when it will be in camping mode, then coffee maker, air pump, and then down the line a refrig. My 100amp solar battery is independent of the main battery (for now) and only gets charged from the solar panel. Since this is my first solar setup, it's more of an experiment. If it turns out I need more power, then I'll upgrade.

It seems like most of what you want to use will be 12 volt (including a future fridge). Build yourself a nice DIY charging station that has lots of USB ports. I have a 12 volt charger for traditional rechargeable batteries (flashlights) so I don't have to use 110. I tend to charge my portable HAM radios with the traditional home chargers vs 12 volt.

I don't think you mentioned if this needs to be in your vehicle or a trailer. That also might steer you one direction or another.

Air Pump - If for an air mattress then yes inverter required - If your vehicle has a 110 outlet then you wouldn't need an inverter for that.
Ween the kids off of TV when camping! Then no power required for that. :)
Coffee there are plenty of options that don't require bringing the counter coffee maker (heck there is an entire thread for this!)

I guess what I am getting at is there are a lot of alternatives to power items via 12 volt vs 110 and sometimes you should just leave some stuff at home. But hey that's me. When I had a 2500 watt inverter I did bring a $9 2 slice toaster. That was some serious glamping.
 
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I recently purchased a 100w Harbor freight solar kit. It has everything except an inverter and batteries. I also purchased two 135 anp. hr., marine batteries. I have no idea what size inverter I should buy to complete the system. My understanding is that I should find out what the largest surge wattage use is, for the equipment I will use , then match that wattage. Can anyone give me a simple answer. Converters are expensive and I'm thinking along the lines of 750 watts continuous, 1500 watt peak modified sine wave inverter. Helpppppp
This guy is s wealth of knowledge about solar power, inverter's and batteries. DIY Solar Power with Will Prowse
 
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