Model 3 electric outlet options

Garyeop_98103055

I have several needs for 110 outlets in my Model 3. CPAC while camping, electronics like games and monitor for kids on long trips, even running a drill and saw on remote land if I can.

I know nothing about electricity. I have a device that plugs in the cigarette lighter and allows me to have a 110 outlet in my ICE. I have read you can not jumpstart an ICE because the Tesla has a small 12 volt battery that is recharged by the main batteries. Here is my question:

Will I be able to power the following from my Model 3 and if so, how?

CPAC
CAMPING FRIDGE
Small monitor and game system
Recharge electric drill
Run 110 outlet saw


I have a solar powered generator. A solar panel, battery, and electronics. My go to answer is to disconnect the solar charger (or keep it in trunk if I have space), use the Model 3 lighter plug to charge this system and then use it for 110 power.

Sof

Here is the info from the owners manual:

12V Power Socket
Your Model 3 has a power socket located in
the rear compartment of the center console.
Power is available whenever the touchscreen
is powered on.

The power socket is suitable for accessories
requiring up to 12A continuous draw (16A
peak).

Warning: The power socket and an
accessory’s connector can become hot

rxlawdude

It's likely the 12V plug device you use doesn't draw more than 12A, which means it will work in the M3. But reading your list of items, it seems that's a helluva lot of power potentially consumed. You can get about 110W of AC (figuring some loss from the inverter), so consider that.

As to what to do when camping to avoid killing the 12V battery, others have discussed ways to allow the car to remain "on" in what is affectionately called "camping mode" that runs the lights, infotainment, and AC. The 12V plug would be active in that mode.

prsist_98050015

Go buy yourself a small Honda generator for your camping needs. The Model 3 is a car, not a power source. That being said, if it works, it works....if it doesn't, it doesn't. Geez that's profound...LOL

Kathy Applebaum

Second the idea of buying the generator. Converting the 12v-12A outlet to 110 gives you 1.3A, which isn't going to power much. By contrast, the smallest generator Home Depot has gives you 30A on 110 -- you could even use it to charge your car if you needed to.

Fishe_98114038

Gas generators are noisy and you have to bring gasoline in your car. This is really a bad choice. The new mitsubishi phev has an inverter built to handle your high amperage 110v needs, a good choice for electric vehicles of the future.

Unknown

Quieter than the saw and maybe the drill I'd guess... but seriously not sure where you'd be going that wouldn't have 110V. Not far from home obviously, as running all of this will soon drain your HV battery.

Frank99

I'm not sure about "running all of this will soon drain your HV battery" - The Tesla batteries have an amazing amount of power.
My home A/C (to cool a 2500 sq. ft house in Phoenix) takes 10KW - a Tesla could power it for 6 hours.
A circular saw takes about 1.5 KW, so a Tesla would power it for 40 hours.
A PS4 takes about 0.15 kw, and a small monitor about 0.03 kw; a Tesla could power them for 300 hours.
A camping fridge (compressor style) might take about 0.010 kw; a Tesla could power it for 5000 hours.

I don't know how much power the onboard 12V battery charger can supply; but I'd guess that anything smaller than 240W (20A @ 12V) could be powered continuously; it's possible the car has a larger charger, but I find it unlikely that you could draw 1000 W (8A @ 120V, 80A @ 12V) without draining the battery i.e. the onboard charger is likely smaller than 1000W.

Garyeop_98103055

@I want to go fast
In the KC area you can drive 1 hour out of town to areas that are the same as they were 100 years ago minus the buffalo plus the chip rock roads.

@Frank99. Thank you for understanding. I will never take a gas generator camping. A solar generator gives enough power to develop a camp shed on wilderness land. I want to make a shower, a tent platform, and perhaps an outhouse.

Point being we will be driving a giant battery pack. It would be nice to have options other than driving in making use of it. Like power backup during the zombie apocalypse. What can I say, I like options without being MacGyver.

Mr.Tesla

Propane generators are the best. Those tanks won't leave any fumes or spills, and the propane doesn't go bad, like a can of gasoline would. Plus, propane burns much cleaner than gasoline.

jefjes_98051056

How about using additional 12v batteries that you've pre-charged at home? You may even be able to hook them up parallel in the frunk and connect them to the 12v charging system for the car's 12v battery to charge/keep charged on the way to the location you plan to use them. Depending on the size, they may last for awhile using an inverter but depending on the inverter load/size, I would disconnect them from the car during use to avoid any problems.

stevea137_98199430

By the sounds of it, the DC-DC converter in the Tesla is quite limited (12A continuous at 12v is only 144W) and is really only meant to recharge the 12v battery and not a lot else. It could probably run one of those devices from your list at a time, minus the AC saw (or the CPAC, no idea what that is. Did you mean CPAP? it would likely run that no problem).

About the best you could do is use the Tesla to slowly charge your solar system on cloudy days, assuming you can limit its draw to less than 140W. Or keep the solar system's battery topped up during the night.

In simpler terms, think of your Tesla as providing about as much power as the solar panel in your solar generator system and then use it accordingly.

Unknown

@garyeop, why would you want to go there :P

@Frank99, I understand the numbers, but you can lose 200mi range overnight with the cabin heater on to keep you warm while you play the PlayStation. To continuously draw 12V power means to continuously have the high voltage system fully energized and consuming energy to support. The lower the device current, the more wasteful the vehicle architecture is when parked idle.

Rocky_H

@stevea137, Quote: "By the sounds of it, the DC-DC converter in the Tesla is quite limited (12A continuous at 12v is only 144W) and is really only meant to recharge the 12v battery and not a lot else."

I don't think it's that. It's the fuse in the path to where you can access it from the 12V socket. That generally uses a 10A fuse. So drawing the most you can through that, and using an inverter to switch it to AC makes 12V 10A into 120V 1A. That is just not much energy to power 120V style devices. Sure, electronics like a laptop or something will do fine, but larger stuff is going to pull more than 1A.

Regarding the Mitsubishi Outlander having it, yes, I think it's a feature that some people want, and it's kind of useful, and it is a little weakness that Tesla doesn't have it. But not every car has every single feature people want.

giskard_98037561

I would have been interested in this as well as I plan to use my Model 3 as an occasional "camper" (the only thing I don't like about camping is trying to sleep in the heat). I have a portable camp fridge/freezer that I do plan on running off of the 12v socket, too. It would have been nice if Tesla included a 12v socket in the trunk are - as it is I'll probably have to get an extension of some sort up to the center console.

Who knows, maybe the aftermarket will come through. It will depend on whether or not they think there's a market and how difficult it is to get access to more power from the main battery.

Coastal Cruiser.

There's a lot of good suggestions here. Picking up on one of them, I think the DYI approach I personally would investigate if I needed a good supply of either 12v DC or 120v AC would be to construct a frame that would fit in the Frunk and be populated with a few 12v Optima BLUE TOP maintenance free batteries. The auxiliary batteries would be wired in PARALLEL.

Then there are TWO ways to use the battery pack.

1) The easiest and most surefire way would be to simply connect one or more 12v outlets, or a beefy inverter, to the positive/negative terminals on the aux batteries. That's it. No connection to the car.

2) The other way would be to connect the aux batteries to the car via the port on the Model 3 for jumping a dead 12v onboard battery. This would require making up a wiring harness that would plug from the batteries to the jump port. The idea here is that you would simply be augmenting the onboard battery with additional run-time. This might be the least intrusive solution in terms of connecting to the car.

The advantage of the latter solution is two-fold; You could use the onboard 12v "cigarette" outlet, and it would simply have much greater run time. Secondly, you _might_ be able to charge the aux batteries when the car is operating. That would pave the way for multi-day road trips. It's probably a warranty killer, but may be technically possible. The aux batteries would simply charge as the car charged the native 12v battery (slower of course).

One caveat for the charging aux battery scenario: You would want to buy the same type of 12v battery used in the Model 3... flooded lead acid, AGM, or Gel Cell (I don't know which type Tesla is using). Each type of battery uses a different charging voltage and the Model 3 12v charger will be tuned for one of those three types.

I would want to learn more about that jump port as well... a) Is it a two-way connection? Will it feed power OUT as well as in. b) What is the current carrying capacity of the wires connecting the port to the battery? Probably not an issue, but you would then know what size fuse to use on your wiring harness that plugs into the port. (safety first).

Gotta love that Frunk!

Daryl_98154534

I bought an after-market kit for my Volt that includes a 2000 W (3000 peak) inverter that could power my refrigerator in an emergency. I've never had to use it, though I've tried it out to make sure it works.

stevea137_98199430

@Rocky_H et al, an important difference to keep in my is the difference in ICE vs Tesla 12V supply.

An ICE 12V battery can supply stupid amount of amperage (think hundreds of amps), mainly to power the starter in short bursts. The alternator in the average ICE vehicle itself can provide 100 amps continuous, and upgrades to 200+ amps are not uncommon. In these cases the 10A fuse to the cigarette lighter is to protect the wiring and socket (which was never designed for high amperage continuous draw).

The Telsa is different however. The 12V battery is just there to power auxiliary low voltage DC systems. The most current demanding of these is probably the window motors. Also, there is no 100+amp alternators for recharging. There is just a DC-to-DC converter. These are not cheap or simple little devices, especially when you are stepping down to 12V from 400V. And they also run at peak efficiency when running at near peak output. So, for example, designing in a spare 50A of capacity that most people would never tap into would reduce overall efficiency by some percentage.

But in the end I am just guessing based on informal EE training and from the "12A continuous, 16A peak" rating on the 12V socket. I'm not going to push it to see what melts first, the 12V socket, fuse, or DC-DC converter

johnmann_98096061

Maybe you could use a generator powered by the Teslas drive wheels. Like the generators that some bicycles use to power a light. I’ve seen these used at backcountry construction sites powered by a truck with one wheel jacked up and placed on the generator’s rollers. I’m not sure whether they are a commercial product or a homemade horror violating nearly every known safety regulation.

Coastal Cruiser.

stevea137, apologies, but I'm not sure that comment adds to the conversation. Most people likely understand the 12v battery in a Tesla is not designed for the rigors of starting an ICEmobile.

Keep in mind the that the purpose of the DC-DC converter is only to charge the battery. It _converts_ ~400v of the battery pack down to a voltage just above 12v in order to charge the 12v battery. It is likely NOT used to power the "cigarette" outlet. There is no need because it is a 12v to 12v connection. That style of outlet is only rated for so much current, and the fuse does as you stated; it protects the socket and the wiring.

If you have specific knowledge that the Model 3 uses the DC-DC converter to power the 12v outlet then please state such and I will withdraw my objection to your comment. ;>

stevea137_98199430

No worries @Coastal_Cruiser, just a conversation about what we could get away with powering off the 12V socket (i.e. could you power a camping fridge off it?).

So charging the 12V battery in the Tesla works like it does in any ICE vehicle. When the vehicle is off, the battery is the power source and provides power for the entire 12V sub-system including 12V sockets. When the vehicle is running, the alternator (ICE) or DC-DC converter (tesla) is providing the power for the entire 12V sub-system. In effect, the 12V battery becomes a drain while the car is on because is it charging. If a large load is put on the system, the battery and DC-DC converter can both provide power to meet the demand until the battery is discharged too far, then the load falls entirely onto the DC-DC converter.

Given the engineering I have seen on some tesla tear downs, I would assume there are breakers or resettable fuses to protect the DC-DC converter rather than letting burn out.

casun

who doesn’t have a solar powered generator?

Rutrow

FYI. From the owners manual, page 106:

"Caution: Do not use the Battery as a stationary power source. Doing so voids the warranty"

:-O

Coastal Cruiser.

Thank you Mr. Rutrow. I nominate you the official "when all else fails read the manual" officer. :>

stevea137 said: "...When the vehicle is running, the alternator (ICE) or DC-DC converter (tesla) is providing the power for the entire 12V sub-system."

Actually you got me interested in the specifics of how this works and I was looking up some info on the Tesla 12v battery. We are down to the "devil is in the details" level, but as you may agree this is a necessary level if one is to really understand what the hell is going on.

I found a few Model S forum threads on the battery. The Model 3 may or may not follow this. One member asserted that the car's electronics are _always_ powered by the 12v battery. When the 12v battery reaches 50% discharge the contactors to the main battery close and the converter simply charges the 12v battery. So that may be exactly what you said, in that a certain amount of current from the main battery finds it way to powering the 12v load, with the 12v battery acting as a buffer. Not too different from an ICEmobile, with the exception that the Tesla 12v battery may drop to a lower voltage before the converter is activated.

RETURNING TO THE OP, given what Rutrow said, i think an external solution to run CPAP machines and the like will need a totally external solution, like one of those portable power units you see for sale that contain a battery and inverter. Only wacko DYI types may attempt the other solution I suggested.

It will be interesting to see if someone finds a nice beefy external power supply that tucks nicely into either the Frunk or the compartment below the trunk. The latter may be the more workable solution in that you could more easily route the power cable to the equipment inside the car.

Coastal Cruiser.

Here is an example of an external power unit on ebay:

ebay
.com/itm/Poweradd-Power-Inverter-100W-12V-dc-to-110V-120V-ac-car-RV-50000mAh-Generator-/282405423230?_trksid=p2385738.m4383.l4275.c10

It puts out 5 amps at 110VAC. It also appears that you could charge it off the car's 12v power socket during the day while the car is in operation.

The seller did not include the dimensions, but the unit looks pretty tiny. may well fit in the frunk/trunk well.

Just an example....

stevea137_98199430

lol, nice find @Rutrow. When all else fails, RTFM.

Interesting info @Coastal_Cruiser, you just blew my mind. I dug around also and indeed Tesla is letting the 12V battery discharge to 50% SOC while the car is off before recharging it. Even with a deep cycle lead acid battery, that is nearly abusive to the battery. Hopefully they have addressed this somehow in the M3, cause I don't feel like having the 12V battery replaced every 12-18 months!

Back to OP, on top of what @Rutrow stated from the manual, DO NOT use your Tesla as a power source unless you like replacing it's 12V battery very often!