Recent content by marcmerlin

Yeah, I couldn't find good info on that. However my main concern is you'd be constantly discharging the battery while the car is running and it'd be constantly trying to charge it. As long as the charging system stays on all the time, current should pass through and you should be fine. But there...

My guess is that you should be fine. I'm pretty sure there is some circuit between the DC-DC bar and the standby battery and therefore you can't just pull a bunch of amps, but 8A should be fine while the car is awake. The car will tell you if the standby 12V battery is dipping too low (although...

Fair point. I made sure the inverter ground was not connected to the negative. I was worried about the DC-DC positive shorting to the chassis anywhere, so I connected it directly to the inverter and taped it carefully :)

There is indeed no right answer on the resistor. You want it as big as possible to slow down the current, but not too big that the relay won't close. This is totally specific to your inverter in your relay, That said, 100 ohms is probably a good place to start (I initially had 1 Ohm and it...

err, isn't it exactly what I'm doing? :)

Inverters have a big capacitor on the 12V side. Capacitors can take mostly infinite current (1000A or more, whatever your wire will allow). This will cause a massive spark every time you connect to a battery. The battery does not care, but the DC-DC in the car does, and it will shut down. So...

Ok, since I can't edit the first message, and my solution is now hidden in the middle of the thread, I'll post it here again: Marc's Blog: electronics - Using a Tesla Model 3 as Emergency Power Source In Case of Grid Failure

I feel ignored :) First, 10 messages to tell me that the DC system cannot be bidirectional when it's the AC system that isn't, and then I wrote twice already that you'd need a battery-less powerwall at home. Powerwalls use 400V-ish, so clearly those inverters exist and are as common as...

Please don't get things mixed up. I am not talking about AC charging, please re-read what I wrote. I am talking about DC charging which can now be done at 250KW, which at 400V is 625Amps peak (it used to be 400A peak, but that was raised recently). I'm surprised that they have enough diodes to...

Ok, fair enough, thanks.

Just to be super clear, are you sure the diodes are on the 400A DC bar? You need some big ass diodes for 400A, and doesn't the video say that the DC current can flow backwards for pre-heating the system when you are driving to a supercharger? Actually, sorry, 250kW for the new superchargers is...

I understand the car cannot generate and output AC, but the DC can be run backwards, can it not? If so, as I wrote earlier, you could get DC from the charge port, and plug that into a battery less powerwall that would convert that DC back into AC and sync up with the AC from your house. Or am I...

you don't need a two way inverter, as long as you can get DC out of it from the charge port, that's enough to plug into some battery-less powerwall and do V2G

Are you sure? Tesla poised to unlock vehicle-to-grid abilities with 'bi-directional' charging systems says "There's logic to allow DC to flow out the battery pack. So you can supply an external grid-tie invertor with that and let it do the rest of the magic. Making it part of the HPWC would make...

You can easily run a 120/240V extension cord out of the door with the door closed. My car is in my garage though, so I don't care either way :)