Sentry Mode and Mileage?

[Linus1]

I have seen a post or two about how Sentry Mode uses power and reduces mileage. My first trial seems odd, so please help me understand if I have things right:

- charged M3RWD to 310 mi
- drove freeway to city 108 mi away (by Google maps).
- parked at hotel, charged up 69 extra mi.
- parked for two days at hotel with Sentry Mode on.
- drove 108 mi back home with only 12 miles left.

Seems I drove 216 mi; charge total of 379 mi; 12 mi remaining.
Is the balance used by Sentry mode really 151 mi?

Not a complaint, just a question.

 

[Linus1]

By the way, nothing was recorded on the thumb drive during those days. I know SM worked because as I walked up to the car I saw it engage.

 

[SMAlset]

But was TeslaCam recording? You need to have the red record dot on the camera icon. You can put your usb in and the camera icon can be there but the red dot doesn't come on in which case you need to put the camera icon to get to start recording.

 

[TiggerTime]

So a number of things could be happening, but Sentry using 151 miles shouldn't be one of them.
Sentry only seems to use about 2 miles/hour when I use it which tends to be about 9 hours while at work.

A number of factors can reduce your total usable miles one of the biggest is how you drive the car.
If you have lead foot then just like ICE cars you burn through more energy reducing mileage.
Freeway driving over 60 mph really starts to eat away at overall mileage.
Weather conditions(temp,rain/snow, wind), terrain all reduce mileage as well.
If you look at your kWh average and it is running above 240-250 or higher then any one or combo of the above are probably the culprit.

I drive majority of the time on roads that are 55-70mph and typically have a kWh around 220. If I am driving a bit more aggressive off the line or higher speeds then I see the jump in my kWh into 300s.

Did google maps take you the same route as the car nav?

If you haven't had the car long then enjoy the driving a bit and try adjusting some things you can control and see if they make a difference.
Either way 151 mile is a lot unless you were really hauling ***
Just some thoughts.

 

[RTPEV]

It would be helpful to know what the range meter said when you arrived at the hotel, after your 69 miles of charge, and before you left the hotel. Without those critical pieces of information, it's hard to say exactly where your range was lost.

Keep in mind, the range meter is not an exact figure (although it's not bad on Teslas). If you drive really inefficiently, you will not get 310 miles out of the car. Having said that, driving inefficiently sometimes means something DIFFERENT in an EV than it does in a gas vehicle. Contrary to what @TiggerTime says, being aggressive off the line is not necessarily inefficient in an EV: the engine doesn't have to rev to get it up to peak torque range; in an EV you have some IR drop losses, but that's about it--it takes the same amount of energy to accelerate a mass to a given velocity regardless of how fast you are accelerating it. Where it gets inefficient is if you are aggressive on the line and then immediately have to slow back down for traffic in front of you or because you came to the next light. Having to use a lot of regen and/or brakes is inefficient. The net is, if you are on and off the accelerator a lot, this is inefficient. And as much as people love standard regen for one pedal driving, low regen is actually more efficient.

I agree with @TiggerTime : monitor your Wh/mile carefully to see what your efficiency is while driving. With highway driving (put your aero covers on if you have them), you should be able to get around 220 Wh/mile (lower is better). If not, you probably are not going to get 310 miles out of the car. And monitor your range estimate before and after you park the car. This will tell you if you have excessive vampire drain (figuring out if it's Sentry Mode or something else is a different exercise).

 

[jjrandorin]

I have seen a post or two about how Sentry Mode uses power and reduces mileage. My first trial seems odd, so please help me understand if I have things right:

- charged M3RWD to 310 mi
- drove freeway to city 108 mi away (by Google maps).
- parked at hotel, charged up 69 extra mi.
- parked for two days at hotel with Sentry Mode on.
- drove 108 mi back home with only 12 miles left.

Seems I drove 216 mi; charge total of 379 mi; 12 mi remaining.
Is the balance used by Sentry mode really 151 mi?

Not a complaint, just a question.

I really really (really)doubt that your "drove 108 miles away (by google maps)" and drove "108 miles back home" was actually only 2016 miles of range used. if I had to guess, I would suspect that your 108 actual miles driven was more like 140 miles range used or even a bit more. Unless you are a very new EV driver, you likely have realized that unless you actually drive like the epa tests, you wont get the rated range.

I drive moderately to work and back most days, on back roads where there are almost no stop signs, and windy roads where the speeds are 30-45, and in my model 3 performance, my 76 mile round trip to work and back drive uses anywhere from 90-110 miles of rated range.

So, sentry mode uses 1-2 miles an hour of range. The rest is you, either the way you drive or using the heat / AC, etc.

 

[Need]

Is 2 days 48 hours? Shorter or Longer? Sentry Mode uses about 1 mile per hour, so you lost about 50 miles there. You have about 100 missing miles. Drove 216, used 316 seems a bit high at Oregon. If you are at somewhere sub-zero with snow... that seems about right.
How fast are you driving? I think to get the rated mile, you need to have a flat ground, somewhat warm temperature, no rain no snow, and drive at 65 mph without turning on heat or ac. And you have to have 18" tires at 45+ PSI with aerocap on!

 

[TiggerTime]

Where it gets inefficient is if you are aggressive on the line and then immediately have to slow back down for traffic in front of you or because you came to the next light. Having to use a lot of regen and/or brakes is inefficient. The net is, if you are on and off the accelerator a lot, this is inefficient.

Thanks for making that clearer than I did.

 

[Linus1]

I drive somewhat reasonably. I am getting over the wow-effect of accelerating from a stop. This trip was Eugene to Portland almost entirely I5, mostly 70mph, late afternoon. Cloudy, 55F, but not bad, and pretty flat.Started at 310 mi and was at about 190 mi in Portland. Added 69 mi at a Blnk charger the afternoon. No driving until third day evening but was at 140 mi. This is where the miles were "lost" while the car was sitting. Same conditions, and same speed back to Eugene except for slow going during rush hour in Portland, but not too bad, surprisingly. Again 70mph, flat and straight. 12 miles left.
By the way, where can I see the kWh average numbers?
And what red dot? The camera icon for backup?