Sentry mode drains ~30km over a work day. Close to 5kWh - that could mean a tow
if you're really pushing it. I could see why they set the limit to 20% to avoid people being stranded and calling Tesla for towing.
They could offer a "waiver" confirmation and log it so you can't rabblerabble when the car dies on the side of the road because you wanted to enable sentry mode under 20%. Like a verbal recording/confirmation with the Right Steering Button to confirm override - "Computer - confirm override to enable Sentry Mode, Alpha 2 6 Beta niner".
Battery longevity management could also be a factor as going below 20% SOC for extended periods of time accelerates the degradation of the battery. Keeping your battery in tip top shape seems to be in Tesla's interest at this point in time.
Both good points. But when plugged in there should be no reason to disable sentry IMO; in fact when plugged in is the main time I want to have it on, because I'm likely out in the public and who knows what mischief may go on when I'm off doing 'stuff'. Like I said above, Sentry is basically idle draw on the car (around 300 W; its the same as just leaving the car on with no climate control running). From my testing, it causes around 2-3 km/hour of range loss, which correlates with the 300W estimate. Plus, the phantom losses which are always present are around 70W, so realistically sentry mode only should be adding around 250W of 'additional' drain on the battery. So I still think that it would take a very long time to drain from 100km down to nothing....plus
Having driving a 60km 'EV' and an '80km' EV for a combined 110,000 km I guess I just find it counter intuitive to think of having 100km (15 kWh) as 'low range'
On the battery longevity side of things, it just strikes me as odd that they would put such a restrictive limit, yet apparently dont care much about the phantom drain from Tesla's compared to other EV's. I'm 'losing' about 80km/week in phantom losses (dont plug in during the day, and I try and let the battery discharge to around 100km before I charge it back up to 90% again, so I can see how much I'm losing over a 2-3 day period and extrapolate that out over the week).....basically it amounts to almost a 'full charge' in a month and a bit. That's around 8 full charge cycles/year. I think Tesla's are rated for 1500 discharge cycles, so this means that over 10 years you are 'losing' 5% of the life of the battery just because of phantom losses. This is one of those strange things I've clearly never really come to peace with about owning a Tesla, hence my rant about it
Contrast this to my wife's Bolt, which I can leave for a week straight and not lose a single km in range, climate remote start works down to much less than 20% SOC, and there is no 'rule' about not charging the battery to 100% (it even says in the manual its ok to do so, but that regen will be limited until ~ 95%). I really, really wish there was a way to put my Tesla into 'coma mode' and not talk back to mothership, etc when its parked during the day/in my garage at night. Its not about 'saving money' on the electricity, but as an engineer/designer it just doesn't make sense to always essentially leave some sub systems in the car on. This will be a point of weakness for Tesla when trying to 'convince' someone that its 'ok' to lose 15-20% of your charge/week. Its like filling a gas tank with a slow, steady leak in it.
That was admittedly a bit of a side bar/rant from the original thread; but I started the thread so its ok to de-rail myself
