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This article has examples of the best automotive inverters. But I'm not strong in this thread. Please give me an advice!
Thank:)
 

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@Marija1204 welcome to the forum from Oregon!

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@Marija1204 I have just completed an extensive search for an inverter to use my other car's (Nissan Leaf) battery as backup power for the infamous California blackouts and have the following advice:
1. Stick with pure sine wave units. They are more efficient and your electronics will thank you.
2. If you are going to do a permanent installation, such as 110VAC outlets in the back of the console, you will need a compact unit that can fit in a small, well ventilated space.
a. keep at or below 300W due to cooling requirements. Consider mimicking the Subaru option. You can probably do it cheaper and better anyway.
3. For occasional use as a direct battery hookup, go big, like up to 3,000W constant power. This will run tools and appliances that have heavy starting loads. No need to be too compact here. spend money on the guts, not a fancy case.
a. consider using a 50A quick disconnect (Anderson connector) permanently wired to the battery.

Happy inverting!

GD
 

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Fully depends on what you intend to power with the inverter, and how it will be plugged/wired into the car.

The DC plugs in the car (at least my 2016) share a 20A fuse, and are individually rated to 10A, which is somewhat confusing. A 150W inverter should work fine in either DC plug, if the device you want to power pulls more than that, hardwire it to the battery with big wires. Your mileage will vary with loads surging over 150W, but continuous shouldn't be a problem at that level.

I have wired my car to power a fridge when driving/parked, and charge a 2nd battery that powers the fridge when camping. Its pretty easy to run wires for larger loads if needed. I considered inverters for both of these purposes, but DC-DC power ended up being the easier way to do it.
 

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2018 Forester XT Limited CVT
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I have just completed an extensive search for an inverter to use my other car's (Nissan Leaf) battery as backup power for the infamous California blackouts and have the following advice:
1. Stick with pure sine wave units. They are more efficient and your electronics will thank you.
2. If you are going to do a permanent installation, such as 110VAC outlets in the back of the console, you will need a compact unit that can fit in a small, well ventilated space.
a. keep at or below 300W due to cooling requirements. Consider mimicking the Subaru option. You can probably do it cheaper and better anyway.
3. For occasional use as a direct battery hookup, go big, like up to 3,000W constant power. This will run tools and appliances that have heavy starting loads. No need to be too compact here. spend money on the guts, not a fancy case.
a. consider using a 50A quick disconnect (Anderson connector) permanently wired to the battery.

Happy inverting!

GD
1. Pure sinewave is preferable, however they are not more efficient. The pure sinewave will cause fewer problems with your electrical loads though.
2. The most important installation issue is the voltage drop along the dc cables between the battery and the inverter. Voltage drop along these cables will cause the inverter to enter low-voltage shutdown during non-insignificant current draw. As an example, if you are going to run a 300 W ac load, you're going to draw approx 30 A from the battery.
3. You're not going to put a 3,000 W inverter in a Forester (3,000 W = 300 A dc draw). A 50 A switch is not going to cut it for more than a 500 W inverter.

For a Forester or similar vehicle, you won't be doing more than charging your phone or running a laptop or similar load, and I'd recommend you have the engine running since the vehicle battery is a starting battery and not a deep-cycle battery.

Find the power draw of the loads you want to run, and then see if the dc socket in the car can supply the current (at a decent voltage). If the socket can't supply the power, you're looking at direct connection to the battery. Remember to size the wire appropriately -- calculate the dc current required, calculate the voltage drop through copper, look up the wire gauge needed to provide the needed (or less) voltage drop, and as close to the battery as possible, install your overcurrent protection, sized for the gauge of wire installed.
 

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2018 Forester XT Limited CVT
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The DC plugs in the car (at least my 2016) share a 20A fuse, and are individually rated to 10A, which is somewhat confusing. A 150W inverter should work fine in either DC plug, if the device you want to power pulls more than that, hardwire it to the battery with big wires. Your mileage will vary with loads surging over 150W, but continuous shouldn't be a problem at that level.
Without breaking out the calculator, you can just divide by 10. A 150 W inverter will draw approx 15 A from a 12 V vehicle system. There is a bit of fudge in this approximation to account for efficiency and voltage drop. Using the sockets will incur additional voltage drop at the contact resistance (between socket and plug).

Also look at the inverter ratings. Some ratings are "surge" ratings, power that the inverter can supply for a short time, limited by the physical electronics and connections, and some are "continuous" ratings, power that the inverter can supply indefinitely given appropriate input, at a given ambient temperature.
 

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2015 Forester CVT
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1. Pure sinewave is preferable, however they are not more efficient. The pure sinewave will cause fewer problems with your electrical loads though.
2. The most important installation issue is the voltage drop along the dc cables between the battery and the inverter. Voltage drop along these cables will cause the inverter to enter low-voltage shutdown during non-insignificant current draw. As an example, if you are going to run a 300 W ac load, you're going to draw approx 30 A from the battery.
3. You're not going to put a 3,000 W inverter in a Forester (3,000 W = 300 A dc draw). A 50 A switch is not going to cut it for more than a 500 W inverter.

For a Forester or similar vehicle, you won't be doing more than charging your phone or running a laptop or similar load, and I'd recommend you have the engine running since the vehicle battery is a starting battery and not a deep-cycle battery.

Find the power draw of the loads you want to run, and then see if the dc socket in the car can supply the current (at a decent voltage). If the socket can't supply the power, you're looking at direct connection to the battery. Remember to size the wire appropriately -- calculate the dc current required, calculate the voltage drop through copper, look up the wire gauge needed to provide the needed (or less) voltage drop, and as close to the battery as possible, install your overcurrent protection, sized for the gauge of wire installed.
Allow me to clarify: Pure sine wave inverters are not more efficient than modified sine wave inverters. Most of the items power by inverters run more efficiently on a pure sine wave current. Efficiency counts on both ends.

GD
 

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Discussion Starter #9
Green Darter

I am very grateful to you for sharing your best practices and experience! 😉🙂I will try to listen as much as possible😌
 

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Discussion Starter #10
asphaltaddict33
Thank you for reply! I want to connect a marching refrigerator, a pump for inflating a mattress and a boat, and some little things...
 

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@Botniklooking

Thank you so much!🙌🙌🙌 I would be very grateful if you could suggest a variant from this list (automotivecraze.com/best-power-inverters-for-cars-and-trucks/) if it is possible, cos I'm not experienced in this and don't understand how to follow your recommendations in the last paragraph😅🙂
 

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connect a marching refrigerator
I'm not familiar with the term "marching refrigerator" - what is it?

It is much more efficient to connect your devices directly to 12V rather than going through an inverter. You can buy 12V charging adapters for all sorts of mobile products be it phones, laptops, iPads (maybe?) etc.. All my devices use 12V except for an inductive cooktop, toaster and kettle that I use on extended trips in the ute.

In the Foz I run a 50 litre 12V fridge and a 300W inverter off an aux 100 amp hour battery.

In my ute I run a 110 litre fridge/freezer and a 3000W inverter off 2 x 110 amp hour batteries.
 
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