Then you might as well just buy a car charging cord for the Macbook that directly plugs into the 12V outlet.
Apple A1172 A1175 charger your MacBook in the car 85w MagSafe 1 AC Adapter Power Supply
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Using an inverter to charge a computer: recommendations? cautionary tales? effect on 12 v battery?
- Thread starter MaryAnning3
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Apple A1172 A1175 charger your MacBook in the car 85w MagSafe 1 AC Adapter Power Supply
I think you are totally right. Based on what I have seen, I am guessing the power port is powered exclusively by the DC-DC converter and that the power port is on if and only if the contactors are closed. I think the voltage there is about 14.9 volts in my model 3.
Mishakim
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It's getting off-topic, but grid-tied solar systems shut down when the Grid is down for more technical reasons than that. Without a battery etc., the Grid is needed to balance the mis-match between the solar power production and the household demand. The details get into pretty advanced power electronics engineering topics.
BTW, you don't need to use an inverter to charge a macbook. The Macbook charges using DC, so it makes sense to go DC -> DC rather than DC -> AC and then AC-> DC. You probably will use slightly less power without the inverter.
https://www.amazon.com/BatPower-CCA2-MagsafeL-Connector-Smartphone/dp/B07JQYXGBH
Fuse I think is 15A, so that makes 12Vx15A=180 watts available. My older macbook uses 85W.
The mod for auto opening/closing drunk must get its power from somewhere.
Do they make 12V mini fridges? Maybe for campers or something? I have heard that normal 120V fridges can be picky about their power supply.
With the PG&E blackouts around Northern CA, this is no longer a joke. My friend, who worked at a solar inverter company said the best way to power your house was through the car's battery. I saw a few youtube vids calling it camper mode. Also read an article that said getting at least a 1kwh inverter would power a fridge. I looked up the specs on my fridge and they recommended at least a 2800kwh inverter. This would be highly useful with these blackouts occurring for the next decade.
You just can't really do it through the 12V system. It would take like 80 to 240 amps to provide that kind of power. Seems unlikely that Tesla built the 12V system for that.
For emergency refrigerator, I would look into a camper fridge, which I would guess would be able to run off of 12V directly and is probably a smaller unit requiring less current.
I've been running two fridges, a fish tank, some LED lights and a couple of phone chargers off a 750W (continuous) inverter through the last two PG&E blackouts without issue. The most the inverter ever showed as draw was 50%, so ~375W. Model 3 SR+.
I did turn on Smart Summon Suspend so that the car stays awake enough to replenish the puny little 12v I connect to in the frunk.
I am guessing the inverter is connected directly to the 12V battery, so the car's wiring doesn't have to bare the load?
Correct, the 12v accessory outlet doesn't come closer to cutting it for this kind of draw, has to be direct too the battery.
There's been some talk about that voiding the warranty on the battery on some other threads. I don't know, seems like not a big deal. Any thoughts on that?
I'd heard such talk too so I contacted support in chat, once they understood that I was connecting to the 12v battery directly and not the "powertrain" battery or the AUX 12v port in the center console they said it was fine. I kept the chat conversation just in case though
I haven't had any errors or warnings from the car, even after running like this for ~36 hours and I'm struggling to understand what kind of problem could come up at this point.Excellent! Thanks for the info. Going to pick up one of those inverters and a smaller fridge as a backup in the garage. After hearing PG&E CEO say that this could be way of life for next decade, it's moved me to being prepared and reading/learning as much as I can about this topic.
Well, what do you know - - - I'm not the only one trying to survive PG&E's little punishing bout with the electricity in my Model 3 battery. (I can understand the need to shut off power during high wind events - it just irks me that we are being punished for the decades of neglect and greed by the PG&E leadership.)
A little bit of history of my Model 3 12V battery:
Shortly after I got the car in February 2018 (VIN ...005641) Tesla fried my drive motor though an overnight update - car was fine when I parked it - next morning everything was dead. I used the emergency frunk opening to get to the 12V battery. It was very dead. So I hooked up my battery charger, since I thought that something had drained the battery overnight. With the charger hooked up the car came back to life again but did not move. After about 15min. of charging I thought that was enough to have the car take over from there. Unhooked the charge - battery dead within seconds. Tried more charging - same results. To make the long story a bit shorter, Tesla told me afterwards that something in the drive motor was shorted out and drained the 12V battery at a very rapid clip - but no smoke or electric smell. They had to replace the drive motor unit. According to the receipt that was all they did, besides checking the tire pressure.
Fast forward to PG&E blackouts:
Having known that the car will survive a super heavy battery drain without any damage, I ventured to hook up a 1100W inverter to power a few necessities in our house. For example as I'm typing this on my desk top computer it is powered by my Model 3.
I tried our refrigerator, but it refuses to start - actually seems to short out somewhat - the inverter indicated 2000W (yup, two thousand) before it shut itself off. Luckily we have a small freezer that works well with the inverter and uses less than 100W - although it goes up to 450 on start-up.
The car so far seems to keep the 12V battery charged up - I measure anywhere from 12.1 to 13.7 Volts during my frequent checks - third day now. I'm keeping the loads low so as not to overtax the 12V charging system.
I had to go to a SMUD (Sacramento Municipal Utility District) powered supercharger to get some more electricity. I live in Placerville, about 30 miles from Sacramento.
Does anyone have any knowledge/data of how much the Model 3 12V charging system can provide continuously?
A little bit of history of my Model 3 12V battery:
Shortly after I got the car in February 2018 (VIN ...005641) Tesla fried my drive motor though an overnight update - car was fine when I parked it - next morning everything was dead. I used the emergency frunk opening to get to the 12V battery. It was very dead. So I hooked up my battery charger, since I thought that something had drained the battery overnight. With the charger hooked up the car came back to life again but did not move. After about 15min. of charging I thought that was enough to have the car take over from there. Unhooked the charge - battery dead within seconds. Tried more charging - same results. To make the long story a bit shorter, Tesla told me afterwards that something in the drive motor was shorted out and drained the 12V battery at a very rapid clip - but no smoke or electric smell. They had to replace the drive motor unit. According to the receipt that was all they did, besides checking the tire pressure.
Fast forward to PG&E blackouts:
Having known that the car will survive a super heavy battery drain without any damage, I ventured to hook up a 1100W inverter to power a few necessities in our house. For example as I'm typing this on my desk top computer it is powered by my Model 3.
I tried our refrigerator, but it refuses to start - actually seems to short out somewhat - the inverter indicated 2000W (yup, two thousand) before it shut itself off. Luckily we have a small freezer that works well with the inverter and uses less than 100W - although it goes up to 450 on start-up.
The car so far seems to keep the 12V battery charged up - I measure anywhere from 12.1 to 13.7 Volts during my frequent checks - third day now. I'm keeping the loads low so as not to overtax the 12V charging system.
I had to go to a SMUD (Sacramento Municipal Utility District) powered supercharger to get some more electricity. I live in Placerville, about 30 miles from Sacramento.
Does anyone have any knowledge/data of how much the Model 3 12V charging system can provide continuously?
Between 200-600Ws. Good to know. I've been watching this guy on youtube - Will Prowse and he does off grid solar DIY systems. I will send him a message to see if he has any solution to our PG&E issues. He mostly puts together small solar systems and tests all types of inverters while living out of a RV. Thing is he recently bought an older Model S, and he's made his own DIY makeshift powerwall.Addendum to the above post:
Did some experimenting - - the 12V battery looses power continuously if I use 600 Watts
Narrowed it down somewhat - the sustaining wattage is somewhere near 250W. I ran our refrigerator and some minor appliances for 7 hours using 245W - the battery got down to 12.0V after 4 hours and stayed there.
Just curious, did you have "Suspend" turned on in the Smart Summon settings?
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