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Vampire drains, 12 volt batteries, parking over 14 days....

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Newbie here. Based on some things I've read about the Model S, some questions for discussion:
  • I've read that a number of Model S owners are going thru 12 volt batteries once a year. Not sure why, but one assumes that there is an issue with the existing architecture of the battery bus system.
  • Vampire drains. We all have them in modern cars, but some cars are worse than others. My concern, parking a Model 3 at the airport for 15 or more days.
  • I know some Model S owners have talked about CTEK (and other) trickle chargers to address some of these concerns. I'd expect a car shipping in 2018 (?) to not require some aftermarket hardware to deal with these items.
Constructive comments most welcome.

Cheers
 
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Newbie here. Based on some things I've read about the Model S, some questions for discussion:
  • I've read that a number of Model S owners are going thru 12 volt batteries once a year. Not sure why, but one assumes that there is an issue with the existing architecture of the battery bus system.
  • Vampire drains. We all have them in modern cars, but some cars are worse than others. My concern, parking a Model 3 at the airport for 15 or more days.
  • I know some Model S owners have talked about CTEK (and other) trickle chargers to address some of these concerns. I'd expect a car shipping in 2018 (?) to not require some aftermarket hardware to deal with these items.
Constructive comments most welcome.

Cheers

Well, you are basically asking people to speculate on a car that isn't going to be available for about 2 years. It would be foolish to assume Tesla isn't constantly working to address some of these concerns.

They already updated the battery system in Model S so that it cannot go completely flat, even if left parked for months... basically the battery will protect itself from complete discharge and can even alert Tesla if it is reaching a critical charge state (such as leaving it in long term storage and the charging cable became disconnected or had a short in it at some point).

It seems that you are worrying about problems that may or may not ever exist on the Model 3. If you are driving your car to the airport where you will leave it for 2 weeks it would seem that the prudent thing to do is make sure that the distance to the airport leaves you with ample charge to get back. The drain per week of the car just sitting there with an untended battery is supposed to be in the single digits.

If driving to the airport will leave you with just barely enough charge to get home then you would be foolish to drive your EV to the airport, take an Uber or a shuttle service.
 
I can't speak to the other points - I've had no issue with my 12V after 50K miles, but as for vampire drain - it varies based on temperature. The worse I experienced this winter was 4mi/day when it was below 0F. But normal rate for me during mild temps has been about 1-2 miles a day. So for me, its been no issue at the airport. Just make sure you have sufficient charge before you go. Of course that's for my Model S. We'll have to see how things differ with the 3.
 
If driving to the airport will leave you with just barely enough charge to get home then you would be foolish to drive your EV to the airport, take an Uber or a shuttle service.

Or hopefully your airport will have lots of Level 1 chargers available. Cheap to install because of the lower power draw and perfect for when the car will be sitting for days/weeks. (The Portland airport currently has 42 of these.)
 
Well, you are basically asking people to speculate on a car that isn't going to be available for about 2 years. It would be foolish to assume Tesla isn't constantly working to address some of these concerns.

They already updated the battery system in Model S so that it cannot go completely flat, even if left parked for months... basically the battery will protect itself from complete discharge and can even alert Tesla if it is reaching a critical charge state (such as leaving it in long term storage and the charging cable became disconnected or had a short in it at some point).

It seems that you are worrying about problems that may or may not ever exist on the Model 3. If you are driving your car to the airport where you will leave it for 2 weeks it would seem that the prudent thing to do is make sure that the distance to the airport leaves you with ample charge to get back. The drain per week of the car just sitting there with an untended battery is supposed to be in the single digits.

If driving to the airport will leave you with just barely enough charge to get home then you would be foolish to drive your EV to the airport, take an Uber or a shuttle service.
The 12V battery has nothing to do with the drain of the main pack. It wasn't a concern whether the main pack will drain with long term storage.

If the 12V battery should die, the car will not run even if your main pack has plenty of energy. Since you won't know if and when the 12V will go. Some have been lucky with Tesla monitoring it and doing a preemptive swap, others have not been as lucky and have been stranded.

The fact that he even knew about the CTEK charger tells me he's done quite a bit of research on the car so I commend him for that.
 
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Newbie here. Based on some things I've read about the Model S, some questions for discussion:
  • I've read that a number of Model S owners are going thru 12 volt batteries once a year. Not sure why, but one assumes that there is an issue with the existing architecture of the battery bus system.
  • Vampire drains. We all have them in modern cars, but some cars are worse than others. My concern, parking a Model 3 at the airport for 15 or more days.
  • I know some Model S owners have talked about CTEK (and other) trickle chargers to address some of these concerns. I'd expect a car shipping in 2018 (?) to not require some aftermarket hardware to deal with these items.

There were some problems early on with 12V battery quality and the charging algorithm. The number of battery replacements has gone down considerably since then (no battery replace for two years now for me).

Unless it's very cold, 15 days isn't even remotely an issue assuming the car is charged to 50% or more when you arrive at the airport (not that 15 days would use 50% charge, but you will want to get home or to the nearest SC if you live a long way from the airport). Many airport parking lots have 120V plugs which would be plenty even on the coldest days. The car wakes up every so often to charge the 12V battery, so that's not a concern the way it is in ICE cars.

Just keeping the car plugged in will do the trick. The trickle chargers are mainly to help a weak 12V battery get a bit more life until it can be replaced (e.g. the owner lives far from an SC). The car warns you when the 12V battery is getting weak (unlike the Prius where one day you can't start) so you have at least a week or three before it becomes critical.
 
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Just keeping the car plugged in will do the trick. The trickle chargers are mainly to help a weak 12V battery get a bit more life until it can be replaced (e.g. the owner lives far from an SC). The car warns you when the 12V battery is getting weak (unlike the Prius where one day you can't start) so you have at least a week or three before it becomes critical.
Thanks.
So understanding what "normal protocol" will be as a new Tesla owner, I shall leave my car plugged in at all times (in my home garage, heated to 10C in winter).
I'll "tell" my new car to only charge up the propulsion battery during off peak hours (1900-0700 daily).
The software may instruct the car to hive off some grid power at any time to keep the 12 volt battery float charged.
Am I interpreting this correctly? Cheers
 
Thanks.
So understanding what "normal protocol" will be as a new Tesla owner, I shall leave my car plugged in at all times (in my home garage, heated to 10C in winter).
I'll "tell" my new car to only charge up the propulsion battery during off peak hours (1900-0700 daily).
The software may instruct the car to hive off some grid power at any time to keep the 12 volt battery float charged.
Am I interpreting this correctly? Cheers
That's how mine works. I set the timer so that the charge will end close to the time I leave in the morning. That lets the battery be at a lower state of charge (SOC) for the majority of the day, and in cold weather it means starting out with a warmer battery (less or no regen braking loss and range loss while the battery heats up).
 
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One more question, dealing with Model S owners experiences with the logic of the navigation software and supercharger selection.

My situation: 182 km one way (from the east) via hwy 401 to the Toronto airport. I want to simply drop someone off and return home. This is a 365 km round trip.

The stipulated range of Model 3 is 345 km. I'll assume this is based on zero wind, at sea level, pressure of 101 kPa and a temperature of 15C.

Even with years of experience of mild "hypermiling" driving my '08 Prius, I'll have to stop somewhere on this round trip to quickly top up at a supercharger.

I have two supercharger options (right now).

The first option is a supercharger located at an interchange off the 401, thus 67 km into the start of my trip (or 298 km into my round trip).

The second option is the Toronto-Lawrence Avenue supercharger. It adds 8 km's to the overall distance, plus one must get off the 401 and navigate thru cicty streets, etc. It would be 161 km into the start of my trip (or 212 km inot my round trip).

With the current Model S navigation and supercharger selection software set-up, can I:
  • insert a route "home", Toronto Airport, "home"?
  • If yes to the round trip option, will the software choose the supercharger stop:
    • 67 km into the trip, or
    • 161 km into the trip which adds some distance and muddling about some streets within Toronto, or
    • wait until I'm 298 km into the round trip.
In other words, how close to "empty" does the current software allow before the only thing "it" thinks about is getting off your direct route and getting to a supercharger?
Thanks
 
With the current Model S navigation and supercharger selection software set-up, can I:
  • insert a route "home", Toronto Airport, "home"?
  • If yes to the round trip option, will the software choose the supercharger stop:
    • 67 km into the trip, or
    • 161 km into the trip which adds some distance and muddling about some streets within Toronto, or
    • wait until I'm 298 km into the round trip.
In other words, how close to "empty" does the current software allow before the only thing "it" thinks about is getting off your direct route and getting to a supercharger?

What it will do is route you to the nearest Supercharger as soon as it thinks you can't make the trip without charging. This means that, depending on what you've set as a destination, it will try to route you to the charging location you are already at. You're probably better off to set the destination to the airport, and then set it to home at the airport. The round trip function is really just to let you know if you should charge during the round trip--most of the time this will be obvious.

Use the trip graph as a better guide to which of the SCs you should use.
 
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Charge at Port Hope coming and going and you will be all set.
According to Tesla, battery phantom drain if not plugged in will be about 1% of charge (~4km) per day. Tesla recommendation is to plug the car in wherever possible.
I figure Port Hope will be the best idea. I did email Tesla's "supercharger comments section" a suggestion to have a few superchargers at the "drop off or pick up" parking garage at Pearson where one pays $5 every 30 minutes to park while waiting to meet someone at the terminal. With the high cost of parking, no one would be hooked up to a supercharger any longer than the actual time to pick up your traveller.
After seeing the plumbing attached to a Model S 12 volt battery, I'm definitely on board with the idea of being plugged in at all times. Cheers.