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MASTER THREAD: Powering house or other things with Model 3

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I read through this and understand attaching a large inverter under the seat causes the safety to trip due to large current inrush. Would a smaller inverter maybe 500 watts be a problem? Also any problems with using a smaller 12v lead acid battery as a float to pre-charge the inverter and absorb any load spikes be a problem?
 
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I read through this and understand attaching a large inverter under the seat causes the safety to trip due to large current inrush. Would a smaller inverter maybe 500 watts be a problem? Also any problems with using a smaller 12v lead acid battery as a float to pre-charge the inverter and absorb any load spikes be a problem?
Using an Aux battery and a DC-DC charger like the one linked below is sure to work well. The 20A version would also work if spliced into the 30A subwoofer circuit instead of connected directly to the PCS terminals under the seat.

 
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Reading through this tread with high interest and thx to the contributors.
Using an Aux battery and a DC-DC charger like the one linked below is sure to work well. The 20A version would also work if spliced into the 30A subwoofer circuit instead of connected directly to the PCS terminals under the seat.

Using that subwoofer circuit is probably much safer (using in-cars over-current protections etc.), right? Now my question is: where can I find a good point to tap from that subwoofer circuit (sorry in case this has been mentioned before)? And also: would a 300W pure-sine inverter work fine on that, or would such a smaller inverter also has a too large inrush current?
 
Reading through this tread with high interest and thx to the contributors.

Using that subwoofer circuit is probably much safer (using in-cars over-current protections etc.), right? Now my question is: where can I find a good point to tap from that subwoofer circuit (sorry in case this has been mentioned before)? And also: would a 300W pure-sine inverter work fine on that, or would such a smaller inverter also has a too large inrush current?
I haven't done it, but if you look at the harness going to the subwoofer, it should be obvious which large wires are +12V and GND. If you peel back the wire loom, you should be able to tap into it an inch or two back from the connector.

I don't think a 300W inverter is that useful, but sure, it should work unless the car doesn't like the inrush when the subwoofer circuit is turned on.

I still highly recommend an auxiliary battery and DC-DC charger, even a small battery. I have a little 35Ah AGM that is easy to move around, like this one: https://smile.amazon.com/Mighty-Max...h+battery&qid=1621095742&s=electronics&sr=1-8
 
I haven't done it, but if you look at the harness going to the subwoofer, it should be obvious which large wires are +12V and GND. If you peel back the wire loom, you should be able to tap into it an inch or two back from the connector.

I don't think a 300W inverter is that useful, but sure, it should work unless the car doesn't like the inrush when the subwoofer circuit is turned on.

I still highly recommend an auxiliary battery and DC-DC charger, even a small battery. I have a little 35Ah AGM that is easy to move around, like this one: https://smile.amazon.com/Mighty-Max...h+battery&qid=1621095742&s=electronics&sr=1-8
Thanks a lot. Now, I hope my following question is not too stupid: but where is actually the subwoofer (and the wires going to it)? It is making such a low noise that I found it a bit hard to locate (sorry, my lack of decent hearing I guess too) ;-)

Yeah, indeed 300W is not that much, but actually I was thinking about using something like that for on camping trips, where I just need to have a small fridge, and some small (usb alike) chargers etc. powered. For that, it makes sense to keep as much as possible of the car's protection circuitry in the loop.

For a battery, to take the initial inrush current, would a li-ion battery like the one for jump starting also work?
like this one:
(not sure whether it charges via the large 12V leads, though).
 
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Thanks a lot. Now, I hope my following question is not too stupid: but where is actually the subwoofer (and the wires going to it)? It is making such a low noise that I found it a bit hard to locate (sorry, my lack of decent hearing I guess too) ;-)

Yeah, indeed 300W is not that much, but actually I was thinking about using something like that for on camping trips, where I just need to have a small fridge, and some small (usb alike) chargers etc. powered. For that, it makes sense to keep as much as possible of the car's protection circuitry in the loop.

For a battery, to take the initial inrush current, would a li-ion battery like the one for jump starting also work?
like this one:
(not sure whether it charges via the large 12V leads, though).
For camping, most 12V electric cooler / refrigerators can run from the car's 12V power port (lighter socket) and draw less than the 120W available there. The car's USB ports can be used for charging phones and tablets and the car kept alive with one of the "camp mode" methods.

The subwoofer in a Model 3 is on the passenger side of the trunk between the wheel arch and the tail light. The driver's side has a cubby instead.

Those jump packs are designed for high current but don't have much energy capacity. That one appears to charge from the input power port (labeled 15V 1A) and they provide a lighter plug adapter. Most others that I have seen charge very slowly on USB. If you wanted to use a power source separate from the car for camping, portable power stations are very popular. Just as an example, this Jackery unit has a 300W pure sine inverter built in. However, it is less than 300Wh, so would be dead in less than an hour if you were using the maximum AC output. Anyway, it's just an example, there are a wide variety of these things with different battery sizes and output options.

 
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Since the Tesla M3 12V battery is charged by the main battery, it should be possible to connect an inverter to the 12V battery to get a long lasting source of 120V power during an outage. Does anyone know how much current the 12V charger can supply?

A potential problem would be over-discharging the main battery. Would the 12V charger shut down when the main battery got low?
 
Not specifically what you're asking - but I have seen an article stating that Tesla is planning on adding a backup power function to the cars. Essentially if you have a power outage, the pack in your car can reverse flow through your wall charger and power your house. Apparently the original Roadster had this feature and it wasn't utilized so they haven't prioritized it on the modern cars.
 
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Since the Tesla M3 12V battery is charged by the main battery, it should be possible to connect an inverter to the 12V battery to get a long lasting source of 120V power during an outage. Does anyone know how much current the 12V charger can supply?

A potential problem would be over-discharging the main battery. Would the 12V charger shut down when the main battery got low?
The Model 3 monitors the charging power used to recharge the 12V battery. If you take a significant amount of power from the 12V battery terminals, it will throw an error. If you want to take a significant amount of power from the 12V system, you should take it directly from the large PCS terminals under the back seat. Please read through this thread, it is all covered.
 
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The Model 3 monitors the charging power used to recharge the 12V battery. If you take a significant amount of power from the 12V battery terminals, it will throw an error. If you want to take a significant amount of power from the 12V system, you should take it directly from the large PCS terminals under the back seat. Please read through this thread, it is all covered.
Is this the case with a Model S?
 
I don't believe so. Likewise my RAV4 EV that uses a DC-DC converter similar to the Model S also does not care / cannot tell if you take power from the 12V battery terminals.
Good to know... I use my Model S jump terminals to provide power to a supplemental 750W inverter. Works well when I need 110V power.

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It can work with a DC-DC converter matched to the battery and charger in the E1500. DC-DC converters may not limit current except to shut off (or worse) when over current. The DC charger in E1500 should have current limit control. The E1500 specifies 48V "nominal" for DC charger input but depending on that battery chemistry and configuration the "actual" voltage required may be significantly higher. 48V "nominal" batteries may require 60V+ "actual" to charge properly
Does anyone know the bolt (nut) size for the PCS terminals under the rear seat? I am thinking maybe M8 x 1.25?
 
I have always thought this should have been built in with our cars. Why buy a powerwall when you can drive your battery around?

Bi directional power flow through electric cars would add a whole new dimension to grid stability.
You’ve answered your own question - because this way they can sell Power Walls!
Since the new Ford F-150 offers exactly this capability as a selling point (use it to power your house, job site or whatever else) it’ll be interesting to see whether Tesla changes direction on this so as to not lose market share. If I were Elon, I’d seriously be weighing potential lost sales to Ford versus how much revenue is made off of Power Walls.
 
My friend hacked his Model 3 to hook up a 2500w inverter to host a concert at a remote location. He just got it finished and we were testing it. My daughter approved it by dancing for us :)

Nice audio setup but you can probably do it without the battery since it's not pulling anywhere close to 2500W. However, you should add a breaker/fuse to the setup. Also, there is nothing in the video that automatically voids warranty which is illegal to do in the US.
 
Would it be possible to use the tesla to power things such as a computer and monitor INSIDE the car. Basically what would the easiest way to power such high wattage appliances. I'm trying to avoid tearing into the car because I feel that this could void the warrenty for the car