While the idle draw is relatively high on Teslas compared to other EVs (even without sentry mode enabled), 7.5% is quite high. I track my stats with Teslamate and it estimates typical SoC loss of 1% over a day.
What I have seen is that the BMS may update its SoC estimate after driving, and I've seen it adjust the estimated SoC up or down by as much as 5% in some cases.
I get that from a planning perspective, it still stinks to have range than you thought you did an hour ago, but it's not all that different from the variation you might get with an analog dial on the gas tank, just that it's much easier to notice and track when it's digital and showed as a precise number.
5% to 7% is pretty normal for me - in both summer and winter. This is just leaving the car in front of my house for a few hours (let's say I don't want to park it in the separate garage).
It's not the end of the world for driving around town with less than my whole family (which is 90% of my driving) but it's definitely annoying to come back to a car with 50% charge and see it with 43. I imagine it would be terrifying for a 20 -> 13, especially with the lack of supercharging infrastructure where I live (Calgary).
Huh, that's quite a bit more than I would expect. You already ruled out the 12V battery in the other thread, but there could be some other factors that would keep your car awake.
Does it only happen when you park in front of the garage at home, or does it also happen if you go out somewhere? For example, it might be struggling to connect to your WiFi at home (if you set it up with your home WiFi credentials) to download updates or upload telemetry, which would keep it awake longer than normal as it tries to make do with kilobits per second of usable bandwidth.
The issues do happen a lot in front of my house (which has very poor cell phone coverage). I've had lessor drops elsewhere.
I was wondering about the wifi myself too. I don't have wifi in front of the house and I didn't configure wifi either; I've actually installed wifi in my garage and left the car inside to see and I would get similar power losses.
I wonder if there is (a) a battery warming issue or (b) an issue because my phone w/ the Tesla app & bluetooth on is too close to the car, leading to it not going into standby mode? I don't think it is the former because it would be categorised differently (and it would not happen in summer). Turning off bluetooth on my phone everytime I come inside is honestly a bit insane and I would put that in the "It's a Tesla App problem"; but I don't hear about that issue from other drivers.
The real unfortunate part is that there is no way for me to get this diagnosed. It's been a problem since I bought the car, but it seems to be getting worse over time.
The typical level 2 charger doesn't have to use HomePlug, but most recent EVs will have a HomePlug modem in order to speak ISO15118 to negotiate the voltage during DC fast charging through the CCS1/2 connector.
The pilot pin that carries the square wave used for J1772 is common to both AC and DC charging, so it's possible for a level 2 charger to incorporate a modem and communicate with the EV.
In many situations it would be an unnecessary expense, but it may become more common even in level 2 chargers in the future since ISO15118 can be used to authenticate the car to the charger for plug-n-charge charging without needing a card or app to authorize the charge.
Ah. I'm thinking of [1] from 2016, when there was a plan to add short-cut evaluation to short-cut comparisons. That avoids evaluating all the terms when not necessary. But that was deferred.
That's pretty much exactly what they're saying in the video.
They show their off-the-shelf dev kit which features a generic omni-directional rubber-duck antenna with quoted 1dB of gain (essentially nothing) and 21dBm of transmit power.
In Rust, you can't implicitly omit fields when instantiating a struct, so it would have to be a bit more verbose, explicitly using Rust's analog to the spread syntax.
Adding support for struct default field values would allow for
- leaving some mandatory fields
- reduce the need for the builder pattern
- enable the above to be written as f(S { hours: 2, seconds: 53, .. })
If that feature ever lands, coupled with structural/anonymous structs or struct literal inference, you're getting everything you'd want from named arguments without any of the foot guns.
Has anyone ever proposed it? It's such a straightforward feature with such obvious semantics ("default field values are const contexts") and impossible-to-bikeshed syntax (`a: i32 = 42`) that I've been meaning to write up an RFC myself for around, oh, ten years now...
Last time I had this conversation[1] the main sticking point were around semantics of private fields, but I am convinced that the maximally restrictive version can be done (only pub fields can be optional) and maybe relaxed later after we get some real world experience. The other thing was about whether the default values needed to be const, but that makes sense as a restriction to me.
Yeah makes sense! I haven’t felt the need for this feature personally, but it feels like it fits with the language pretty well to me. The big issue with default values (as far as I’m concerned) is for them to always have a default value, and this doesn’t change the opt-in nature of the concept.
The issue I have with Default is that the verbosity jump from derive(Default) to impl Default for Type is high, evej if you just want to specify a single field. The other reason I want this is because it makes defining builders almost trivial for any case where custom logic isn't needed for the fields. I would expect the impl-based builder pattern to become more niche if we had this feature. Your reason is yet another that would be nice to address as well. I like how this one change addresses multiple things at once.
Yeah, full agreement here. I almost said something along the lines of "it's almost like extending #[derive(Default)] with serde-like attributes to control which fields get what defaults, but with nicer syntax," but got a little lazy with it since we're in agreement anyway. It is annoying that deriving Default is all or nothing.
I didn't even think about the builder thing, but you're right there too.
As hinted at, but not elaborated on by the first part that mentions temperature monitoring, those wires in free air expand and contract with temperature changes. The cables need to be able to support their own weight without collapsing or touching other conductive objects like other cables or trees.
Adding more conductive material helps with the resistive losses, but also makes the cable heavier. Using an advanced cable that has better tensile strength for the same or better conductivity accounts for those second order effects better than just adding more aluminum.
Taxes in the US are locality sensitive. The county sales tax rate varies by almost a full percentage between counties where I live, so depending on whether I ship something to my home or to the office, the amount of sales tax due is different.
I think it's also worth pointing out that the US doesn't have VAT. In Europe, VAT tax averages over 21%. And this increases even further if you have locally imposed taxes. This substantially impacts purchase price.
In the USA, all sales taxes on your item added together are usually just a few percent. (Higher in expensive cities though)
I've observed that Comcast takes advantage of the separation of "fees" into a separate category to increase fees while keeping the service rate the same, allowing them the flexibility to raise prices even if the customer is on a contract that specifies a fixed promotional rate.
So it seems like the current breakdown of charges gives rise to transparency in price, but only because it's in Comcast's favor when it comes to adjusting the numbers. I'm not sure that Comcast would bother continuing to break things down if it no longer gives them an edge.
If they want to break these out they should be optional.
I get broadcast TV with an antenna and would have no need to get it with a television service although somebody who has worse reception or doesn’t want to set up an antenna reasonably could.
Sports are the most popular thing on TV but still a bit more than 50% of people don’t watch sports. Sports fans are often complaining that the offerings don’t meet their needs, whereas people who don’t watch sports are paying for expensive channels they don’t watch. We could have something better but the current system of non-competitive competition (no real differentiation between linear and TV offerings) gives people no real choice except walking away, which in the long term they are.
Setting aside issues that can be safety related where consumer equipment overlaps with legacy equipment, there is a tragedy of the commons effect to not attempting to regulate radio power limits.
It's incredible how well WiFi works for the amount of power it uses.
Obviously turning up the transmit power makes it better... for that one person. For everyone else, that channel has a little bit more noise than before, making it harder to receive their signal.
So maybe their neighbors will also want to increase their transmit power to get better range / speed again. Having a limit across the board for all mass manufactured devices prevents an escalating spiral of vendors selling 30, then 40, then 50dbm etc routers.
As mentioned elsewhere, different countries have different power limits, but it's more economical to make a single radio for all markets with software power limits. One hypothetical way for a vendor to get a market advantage is to sell a radio that is software limited, but wink wink can be patched with easily googled instructions to increase the power to work better. Maybe by downloading a tool from some sketchy website that even actually works and can be spammed across the internet or social media.
So the FCC has to strongly discourage anything that could lead to lots of radios deliberately exceeding the regulatory limits and disproportionately making the spectrum worse compared to a compliant device.
I don't think that necessarily justifies rather invasive schemes like geolocated AFC, but preserving the use of the radio spectrum so that everyone can make efficient use of it is the FCC's mandate.
> It's incredible how well WiFi works for the amount of power it uses.
Actually, WiFi disproves that we'd have a tragedy of the commons.
> Having a limit across the board for all mass manufactured devices prevents an escalating spiral of vendors selling 30, then 40, then 50dbm etc routers.
No, the AP and the device both have a strong interest to limit the power used: not just to limit interference with other devices inside the home, but also to increase battery life!!
> but wink wink can be patched with easily googled instructions to increase the power to work better
I just don't understand why most posters here assume the worst by default. Most people are nice and want to obey the law.
WiFi proved that very little legal oversight was necessary to make it work.
In fact, it did the opposite: by comparing the efficiency of the use of the 2.4Ghz band (noisy with microwaves etc) to the rest of the spectrum managed by the heavy hand of the FCC, any reasonable person would argue for removing regulations or more parts of the spectrum (starting maybe with the huge chunks waste on HAM radio!)
> No, the AP and the device both have a strong interest to limit the power used: not just to limit interference with other devices inside the home, but also to increase battery life!!
For home routers this is a weak argument. Since most people download more than they upload, you could probably send a weaker signal from mobile devices and drown the air with signal from anything plugged into a wall socket.
> I just don't understand why most posters here assume the worst by default. Most people are nice and want to obey the law.
Maybe it's just where I live, but I don't see that on the road (people risking accidents to gain 30 seconds). People will only follow the law if they think it's worth their inconvenience and lots of people weight this in a bad way.
How many hand-tuned APs does it take to make a whole building lose significant bandwidth? After this the regulation has to become looser so the legal devices can keep working, and it never really gets better.
> you could probably send a weaker signal from mobile devices and drown the air with signal from anything plugged into a wall socket.
How exactly is your mobile device going to ACK those received packets? The mobile device needs to transmit as loudly as the AP for its ack to be received.
Boosting the transmit power higher than your receiving device can transmit leads to very bad wifi links, where the mobile device is receiving a good signal but it's own messages are not received back.
You can use different modulation rates to/from a device (this commonly happens). Lower modulation rates give you better SNR, letting your quiet client do slow weak ACKs to loud large chunks of data from the router.
It's been a while since I've tolerated the git gui interface, but when I used to use it, the line-to-chunk logic would regularly fail on short 2-3 line spans.
There's a stackoverflow discussion [1] that suggests it was fixed in 2018, but for many years it was a terrible experience that pushed me to use other frontends just for reliable partial staging.
What I have seen is that the BMS may update its SoC estimate after driving, and I've seen it adjust the estimated SoC up or down by as much as 5% in some cases.
I get that from a planning perspective, it still stinks to have range than you thought you did an hour ago, but it's not all that different from the variation you might get with an analog dial on the gas tank, just that it's much easier to notice and track when it's digital and showed as a precise number.