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How many amps can you get from the 12V system for emergency situations?

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First time poster here, don't have a Tesla yet but I'm researching my next EV. A Model Y (which I assume to be similar but not identical to a 3) is a strong contender thanks to this thread, since I live in a community that has power outages several times a year. (The Ioniq 5 / Kia EV6 newcomers look like potentially strong competitors, and will have this functionality built in. I'm very likely to prefer the Model Y if I can make this work.)

The one thing that I don't see covered is whether this mod takes power from a place in the system where it plays well with the Tesla charge management. (Not sure if it just watches pack voltage, or counts kWh in and out.) Depending on where the system is tapped, this may be a load that the car is not expecting to see. Has anyone actually done this, run some substantial loads for days, and seen that SOC tracks as expected? No alarms or codes thrown? It would be a real pain to go through all this, especially after having partially based the decision on buying the car on its success, only to find there is some unexpected glitch or failure when you really need it. I'm also rather interested in how much system overhead (consumption) the Tesla adds while in Camp or Sentry Modes.

Bottom line - has this been thoroughly tested and proven effective? Anyone tried it on a Y and found differences in installation?
 
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First time poster here, don't have a Tesla yet but I'm researching my next EV. A Model Y (which I assume to be similar but not identical to a 3) is a strong contender thanks to this thread, since I live in a community that has power outages several times a year. (The Ioniq 5 / Kia EV6 newcomers look like potentially strong competitors, and will have this functionality built in. I'm very likely to prefer the Model Y if I can make this work.)

The one thing that I don't see covered is whether this mod takes power from a place in the system where it plays well with the Tesla charge management. (Not sure if it just watches pack voltage, or counts kWh in and out.) Depending on where the system is tapped, this may be a load that the car is not expecting to see. Has anyone actually done this, run some substantial loads for days, and seen that SOC tracks as expected? No alarms or codes thrown? It would be a real pain to go through all this, especially after having partially based the decision on buying the car on its success, only to find there is some unexpected glitch or failure when you really need it. I'm also rather interested in how much system overhead (consumption) the Tesla adds while in Camp or Sentry Modes.

Bottom line - has this been thoroughly tested and proven effective? Anyone tried it on a Y and found differences in installation?
1) no, I have not tested this for multiple days until the battery is near empty. If you use camper mode to keep the car awake, it's supposed to self shutoff until the battery reaches 20%, but I didn't test it
2) in your case, if i's for frequent use, I honestly recommend a powerwall instead, or some EV that actually supports V2G (vehicle to grid). What I did is a hack for very occasional emergency use, and you have to run extension cords to your car, etc... You'll be much better off with a better solution that's designed for this.
 
1) no, I have not tested this for multiple days until the battery is near empty. If you use camper mode to keep the car awake, it's supposed to self shutoff until the battery reaches 20%, but I didn't test it
2) in your case, if i's for frequent use, I honestly recommend a powerwall instead, or some EV that actually supports V2G (vehicle to grid). What I did is a hack for very occasional emergency use, and you have to run extension cords to your car, etc... You'll be much better off with a better solution that's designed for this.
Here are a few new vehicles that are bi-directional and will support V2G charging:

Sono’s CEO Laurin best explained how the company decided to include AC bi-directional charging rather than DCFC:
We always asked ourselves, if this is a solar car, why not be capable of giving power back? So we came up with this idea of bi-directional charging like a power bank on wheels. It can either charge other vehicles or you can plug it in at home and replace your home storage. Or… long term thinking, stabilize the grid in a vehicle to grid way of thinking. Everyone else is the EV industry is working on DC bi-directional charging, but for consumers this is not very helpful because of the high cost of components and availability of them.
Kia has unveiled today the Kia EV6, an electric crossover based on the Hyundai E-GMP platform, and the specs are basically the same as the recently unveiled Ioniq 5, but in a different package.

Last month, Hyundai unveiled the Ioniq 5, its first new electric vehicle designed on a new E-GMP electric platform. The vehicle impressed with a flexible electric powertrain with several choices of motor and battery pack configurations as well as a lot of interesting features, like DC fast-charging at up to 350 kW and bi-directional charging.
 
The other thread has more info, but you can find the solution I came up with on this page:
as well as a discussion that starts after my solution on page #3:
 
Tesla on the other hand... Tesla voids your warranty if you try to power your home with your electric car battery pack - Electrek

Tesla is voiding your warranty if you try to power your home with your electric car battery pack – something that more people have been looking into following power outages in some areas in the US.

While Tesla vehicles are not equipped with bidirectional charging enabling vehicle-to-grid or vehicle-to-home features, there’s actually a way to power some devices using your Tesla vehicles. It’s as simple has plugging a 2,000-watt inverter to your car’s 12-volt battery. Update: As Tesla hacker green points out, it is better to connect to the 12-volt system through the penthouse under the backseat.
 
Please stop replying on this thread, we're trying to close it and I'm trying to post the last message with my solution:
The other thread has more info, but you can find the solution I came up with on this page:
as well as a discussion that starts after my solution on page #3:

There is not clear agreement on whether it's best to connect directly to the DC-DC system or the 12V standby battery, but honestly if you're going to be pulling 100A+, it seems pretty obvious to get from the source with the thickest cable you can, not and all the way downstream on a standby battery with wiring that was never meant to carry 100-200A
 
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