Hello Tesla experts. I’m almost positive I will be getting a model 3 in the next year when my current ice car lease is up. I’m in the market for a refrigerator for my car for occasional use. Any 12v power implications I should be aware of before buying a particular fridge? Amperage? Wattage? Other logistics? Kindly advise
Dometic refrigerator in model 3
- Thread starter Bourbon
- Start date
M109Rider
Active Member
From what I know of the these, it should work on the 12v power supply in the console, but I guess it would depend on the draw.
Good question.
tschmidty
Member
I use this one which is a much better price and works well, but I couldn't say how the 12v works. Supposedly the 12v battery is charged via a dc-dc converter so theoretically it would run off the main battery for quite a long time, but I am not aware of anyone who has tested it.
https://smile.amazon.com/gp/product/B07B8D1M3D/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Edit: the 12v is rated at 12amps. The fridge I linked draws about 7 when running so should be fine as far as it goes, but again would be curious about the actual useage.
https://smile.amazon.com/gp/product/B07B8D1M3D/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
Edit: the 12v is rated at 12amps. The fridge I linked draws about 7 when running so should be fine as far as it goes, but again would be curious about the actual useage.
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SSonnentag
Rocket Scientist
The Dometic only draws around 5A (60W), and runs intermittently, so it's no problem at all to operate off the car's 12V outlet. However, the outlet goes dark when the car is parked. Just be aware of that fact. I wish there was an override to keep 12V power while parked.
insaneoctane
Active Member
SSonnentag
Rocket Scientist
Not an issue with the Dometic or Engel 12V refrigerator/freezers.
It also seems that the Model 3 may keep the 12V outlet hot when the car is off instead of going off after 10-20 minutes as the Model S outlet does. The rear Model X outlet is reportedly always hot as well. Hmmm, still wishing for that feature in my S.
Rough calculation. 3LR battery is about 75 KWh.
With power conversion, refrigerator takes less than 100 Watts. 8 Amps @ 12 Volts = 100 Watts.
If refrigerator runs non-stop, it would use about 2.4 KWh per day. 24 hours x 100 Watts = 2,400 Watt-hours.
That’s just over 3% of battery capacity per day for worst-case non-stop cooling.
Sometimes there’s no substitute for size.
Our contractor had already done the math. Said he would snap up a BEV pickup like the Rivian. He could operate his power tools all day without the noise of a generator. He also noted that Chevy has recently offered 110 Volt outlets in the bed/ tailgate area.
With power conversion, refrigerator takes less than 100 Watts. 8 Amps @ 12 Volts = 100 Watts.
If refrigerator runs non-stop, it would use about 2.4 KWh per day. 24 hours x 100 Watts = 2,400 Watt-hours.
That’s just over 3% of battery capacity per day for worst-case non-stop cooling.
Sometimes there’s no substitute for size.
Our contractor had already done the math. Said he would snap up a BEV pickup like the Rivian. He could operate his power tools all day without the noise of a generator. He also noted that Chevy has recently offered 110 Volt outlets in the bed/ tailgate area.
The 12V outlet draws power from the 12v battery. I assume the frig will draw from it.
The 75kwh battery runs with 400v.
In a ICE car, 12v battery is charged via alternator. Anyone know how does the 12v battery get charged in a Tesla? Is there an alternator like ICE cars? Or is there a transformer that charges the 12v battery from the big battery?
The 75kwh battery runs with 400v.
In a ICE car, 12v battery is charged via alternator. Anyone know how does the 12v battery get charged in a Tesla? Is there an alternator like ICE cars? Or is there a transformer that charges the 12v battery from the big battery?
I use a Mobicool 12v cooler in mine, had no problems .
It does not have a compressor, some type of fan setup but keeps my drinks and food cold
Been using it for years on road trips in lots of cars, I made a lighter plug extension with heavy duty wire and ran it to the trunk
It does not have a compressor, some type of fan setup but keeps my drinks and food cold
Been using it for years on road trips in lots of cars, I made a lighter plug extension with heavy duty wire and ran it to the trunk
The car periodically recharges 12 Volt battery from the main battery.
This will continue until main battery reaches minimum charge level. Then 12 Volt battery can discharge until electronic controls cannot operate. This takes weeks.
At that point car is unresponsive. Cannot even accept recharge for main battery.
Then one must attach jumper cables to provide external 12 Volt power for electronic controls.
That is why Tesla suggests keeping car attached to external power when it will not be in use for long periods.
Thanks for the info man.
When you say it periodically, i hope it means that it monitors state of charge or voltage on the 12v battery. So basically, it is not possible to drain 12V battery, as long as the main battery is in a healthy state of charge?
That’s correct. The 12 Volt battery drops to a certain level and then is recharged.
There’s a long thread in the S forums about trickle chargers to sustain 12 Volt battery at optimum charge level when car is parked at home.
Also, be careful if you connect a cable to tap the car’s 12 Volt system. The system tracks power used to charge the 12 Volt battery vs. power pulled by the 12 Volt circuits. If you connect to the battery and pull significant power, there will be a discrepancy.
It will look like the 12 Volt battery has internal short and is degrading. Soon the car will alert to replace the battery.
If you attach to the power distribution block, the drain is metered. No discrepancy, no false alerts.
Learned the above while figuring out how to connect a high-capacity AC inverter in our S. Son-in-law had plans to run two sous vide cookers for a high-visibility tailgate party.
