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On a non-OEM installation of a 1000 w inverter "us[ing] 4 AWG wire directly to the 12V battery posts with a 100A fuse on the positive terminal, and replaced the switch on the inverter with a relay that's only live when the car is "on" (fed from the fuse box relay that controls the 12v centre console outlet)", a user on a Tesla Motors Club forum question, green1 posted, as relevant herein, the following photo:

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A question that is probably more generic, and a greater pool of mechanics.SE users of all makes may have better answers to is what's the best budget 2000 w pure-sine inverter?

If I'm not mistaken a pure-sine inverter will provide effectively the same electricity like a wall outlet with the 2000 w constraint.

My search for products so far turned up this on Amazon, not sure if this would be good:

EDECOA 2000 Watt Pure Sine Wave Power Inverter DC 12V to AC 120V 110V Power Converter with LCD Remote Controller 2 USB for RV Caravan

Secondly (and secondarily) is there a good installation video, maybe photo guide or, worst case, at least detailed walk-through somewhere available?

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This forum is not the proper place to ask for shopping recommendations.

But here are some criteria for pure sine wave inverters you may be interested in:

  • Wattage (you specified 2000 W already)
  • Size and weight
  • Cost
  • Noise level when idle
  • Noise level when loaded
  • Idle power usage
  • Efficiency when loaded

Often, you may not find reliable information for different products for all of these items. Choosing a good name brand and not a cheap Chinese brand would be wise, because these inverters have electrolytic capacitors and Chinese companies are notorious for using poor capacitors. Of course an inverter from a reputable company such as Victron Energy will cost a lot more.

But then another question: do you really want to have 2000W inverter?

2000 watts at 90% efficiency if the battery voltage drops to 11 volts under load means you are loading the battery with 200 amperes.

If we assume that the car has about 40 Ah lead-acid battery, then the current draw rate would be 5C. That's a lot. And I mean a lot. Especially for a non-deep-cycle battery that will be severely hurt by that current. For a flooded non-deep-cycle lead-acid battery, expect the battery to be destroyed in about 2 minutes, much faster than you'd expect, due to Peukert's law. Yes, destroyed. Non-deep-cycle batteries don't like deep discharge. Even deep cycle batteries don't like deep discharge. With a deep cycle flooded 40 Ah battery, I wouldn't use the 2000W inverter with a full load more than about 1 minute.

If you only use the inverter with Tesla's DC-DC converter on (power on in the car), then the situation changes a bit. You can draw at most the capacity of Tesla's DC-DC converter without putting strain on the battery. If Tesla has 2000W DC-DC converter (I'm not sure, please check this), then you may draw little less, let's say 1800W, without putting any load on the small lead-acid battery.

Also, please note that if Teslas have 2000W DC-DC converter, it may not be rated for continuous duty full load. It's possible it can over a long time output something less, like 1000W, and the 2000W is only for short bursts. By using it continuously at 2000W, you may void your warranty.

Note however that Teslas are very "automatic" cars. I don't have a Tesla but if I had, I would be asking the question whether the DC-DC converter is automatically turned off if the car doesn't sense the key in vicinity. I understand that Teslas don't even have a power button, so it somehow automatically decides whether power should be on or off. If it automatically decides power should be turned off, you have 1-2 minutes until the small lead-acid battery is destroyed.

Also 200 amperes requires very thick wires. Even the best jump start leads you can find might not be thick enough for 200 amperes continuous. Yes, they provide 1000 ampere bursts but only bursts. For continuous current, you will need very thick wires for 200 amperes. This shows that 2000 watts at 12 volts is insane. For that wattage, you should really be using a 48 volt system.

I would be instead looking at 600 watt inverters. They aren't as insane as 2000 watt inverters if using 12 volt system. 600 watt inverter can perfectly well continuously run with 10mm2 wires. 1000 watts at 12 volts should have 25mm2 and that's getting bit large and expensive already.

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  • This is so much more than I expected. I’ll try to follow the instructions I got for the closure and post an on-topic question that relates to the problem I’m trying to solve. Plan A is the car's DC-DC converter (2.5 jw rated) of which the car may use like .5 kw. I intend no greater continuous use than 1.5 kw, and I realized that one at 1.5 kw allows for peak use of over 2.5 kw so really, the inverter will not need to be 2 kw, but 1.5 which many Model S owners confirmed to be safe for use. But seeing the apparent exponential increase in the cable area, I'm assuming it would take like a 56 mm2. Sep 25, 2022 at 17:23

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