So there is a lot of debate in the forums about how large a circuit to install for the UMC or whether to install a Wall Connector or not. Some folks advocate that not very much charging current is needed. Others lobby for as high power of charging options as possible.
As the weather has turned colder here in Portland Oregon (which still does not really get that cold) I have been warming my Model 3 LR RWD before I leave the house by using the Tesla app. I have then been using my Sense Energy Monitor to see how much power the car is drawing. (note that I have a Wall Connector on a 60a circuit so my car can charge at a full 48a)
Here is a graph of usage this evening as I fired up the heat to give a friend a test drive. The car had been cold soaked as it had not been driven in about 24 hours. I think the cabin reported 49 degrees Fahrenheit before starting HVAC. The car was charged to 80% the day before when I got home from work and had drifted down to 78% as it does most days overnight. The car did not attempt to charge the battery while it was heating. I did not give it a chance to warm up fully before we hopped in and went for a drive (regen was limited still and the cabin was not fully warm).
The key takeaway here: The car is able to make use of 10,500 watts of power just to heat the cabin (and maybe the battery?). That is about 44 amps of current at 240v!
So if you don't have that much shore power available, I am curious what the car does?
Does the cabin / battery warm up slower due to limited shore power?
Does it use battery power to heat up instead?
Regardless, I find this to be interesting data! I personally love having the ability to pre-warm the car and battery off shore power and I am happy with my Wall Connector install on a 60a circuit. ;-)
This is the same graph, but with the cursor selecting the house baseline load before the Tesla started charging.
Basically my callout is that just because you can fully charge your car for your milage needs overnight on some smaller circuit does not mean it is the optimal solution.
If the car does presumably use battery in order to bring the interior up to temp then you are putting more wear and tear on your battery (charge/discharge cycles) than is necessary.
As the weather has turned colder here in Portland Oregon (which still does not really get that cold) I have been warming my Model 3 LR RWD before I leave the house by using the Tesla app. I have then been using my Sense Energy Monitor to see how much power the car is drawing. (note that I have a Wall Connector on a 60a circuit so my car can charge at a full 48a)
Here is a graph of usage this evening as I fired up the heat to give a friend a test drive. The car had been cold soaked as it had not been driven in about 24 hours. I think the cabin reported 49 degrees Fahrenheit before starting HVAC. The car was charged to 80% the day before when I got home from work and had drifted down to 78% as it does most days overnight. The car did not attempt to charge the battery while it was heating. I did not give it a chance to warm up fully before we hopped in and went for a drive (regen was limited still and the cabin was not fully warm).
The key takeaway here: The car is able to make use of 10,500 watts of power just to heat the cabin (and maybe the battery?). That is about 44 amps of current at 240v!
So if you don't have that much shore power available, I am curious what the car does?
Does the cabin / battery warm up slower due to limited shore power?
Does it use battery power to heat up instead?
Regardless, I find this to be interesting data! I personally love having the ability to pre-warm the car and battery off shore power and I am happy with my Wall Connector install on a 60a circuit. ;-)
This is the same graph, but with the cursor selecting the house baseline load before the Tesla started charging.
Basically my callout is that just because you can fully charge your car for your milage needs overnight on some smaller circuit does not mean it is the optimal solution.
If the car does presumably use battery in order to bring the interior up to temp then you are putting more wear and tear on your battery (charge/discharge cycles) than is necessary.