Detecting Electric Vehicle (EV) devices



I specifically purchased Sense since my electric usage has doubled since I got my Tesla and the numbers aren’t adding up. Detecting my charging usage is a critical use case for me.

Speaking of which, @MattAtSense when can I expect Sense to accurately detect my charges? It was only detecting the first 30 seconds up until two days ago and not it stopped completely. I have a 2015 85d charging with NE-50 plug. It’s been 2 months/



One step backward, and now a couple forward… Support suggested that I delete my EV (Tesla Model S) after detection and associated logging went askew after my first fairly successful detection. I deleted it on March 23rd and it reappeared as a new detection yesterday morning at 5:14AM soon thereafter successfully identifying and tracing the entire charge cycle for my wife’s car. This time the power assessment was much closer to what I think it should be, vs. last time when it seemed to be coming up 4-5kW short.

A few happy utilization photos (below), plus a question. The Device screen says that the charger was on 17 times this month for an average of 1h 17min, giving a total usage of 241.2KWh. But if I expand the Power Meter screen for the EV device to look at the whole month, I only see one spike, the one early this AM. Do I interpret this that your cloud based-calculation went back and did the monthly summary statistics with the updated model, thus seeing the what seems to be the correct number of charges and aggregate energy usage ? Or are the monthly summary stats for the EV device garbage ? Hoping that they are somewhere near accurate since the number of charges (17) and average length (1h17m) seem about right, though the average wattage (12.2KW) seems low (we always charge around 20KW).

Thanks for the continued hard work,


I have a Model S and a Chevy Volt. neither are identified in my Sense. Basically only a handful of devices are identified. For the most part I have a giant unidentified blob. Wondering when will detection improved. I’ve had my Sense for almost a year.


My Sense appears to have reliably found my 2013 S85, charging at 35 amps.


@mp3tocd_man: Awesome! Congrats.


How are you charging?


So the firmware upgrade must have done something to improve EV detection somewhat as it recognized my Tesla charging for the first 21 minutes but then stopped. This is as opposed to the 31 seconds it used to detect.

Edit: back to just the 30+ seconds a day later. Sigh.


**> strong text**Hi all. One month into a data reset (after 5 months of initial operation) and my 2017 i3 has not been recognized. It’s so darn curious to me how a 200W refrigerator light an be recognized but a very large ~8kW charge consistently after 9pm can be missed (5 months + 1 month). Anyway just an update…


Matt wrote:

Over the coming weeks, we’ll be releasing device detectors for … other EVs.

This is great news. I’ve had my Sense installed since January and it has yet to identify our nightly charging of two EVs. They are both uncommon (a Th!nk City and a Vectrix) and both are submetered, so please let me know if I can help in any way with your detection and/or calibration.

Related question: There have been several reports concerning “drop outs” of various devices, when they become active but Sense misses them. Are you testing against any form of ground truth, e.g. submetered devices? I expect this would be very helpful toward improving your detection accuracy, and expect there’s many in this group with submetered data for a variety of device types. Myself included.

-Steve at


Any Model X owners out there whose Sense has successfully detected their vehicle? I’m expecting delivery of my X 100D within the next few weeks and am wondering if the Sense will detect it.


Not yet for my X. So far Sense only sees our S.


Just wanted to report for the first time, Sense detected a full charge of 15.3 kWh of my 2015 85D using my NE14-50 plug. This number matched the 15.4 reported. Teslafi says it was charging at 40amps but I don’t think that’s accurate as I’ve always hovered between 30-36. The math seems to say 36amp.



I’ll log a ticket with support and send you a PM with what we find.



Apologies in advance for posting this if it’s too off topic. I’ve posted this on but haven’t gotten an answer and this is the only other place I know a bunch of Tesla owners hang out.

While I await delivery of my X 100D in a few weeks, I’m planning the changes needed in the garage to accommodate charging. Installing the charging cord on a wall is not a great option for various reasons. What I’d like to do is mount a reel on the ceiling similar to the way I have an air hose (from a compressor in the attic above the garage) and an electrical extension cord mounted on the ceiling. The cord is pulled down from the reel when needed and then when finished, a slight tug on the cord and it retracts into the reel and out of the way. I plan to use the 20’ cord that comes with the Tesla and a socket installed by the electrician in the ceiling to plug the cord in to.

I have been searching for reels that can have a user-supplied cord mounted to them and the best thing I could find costs upwards of $500. I have also read articles that warn about winding the cord around something because of heat dissipation issues.

Has anyone encountered and solved this problem, or have suggestions? A link to a ceiling mountable reel at a reasonable price would be appreciated. I’m not looking for a $20 solution here, I know I may have to spend a few hundred dollars, just would rather avoid $500 if at all possible, not to mention wanting to avoid the risk of setting my garage on fire.


Here’s a potential idea - why does the cord have to reel up? Why not have a line that reels up attached to the cord. That way it’s still up and out of the way, but you can pull down/release up as needed? Does that make sense?


Sorry, I don’t follow. Contact me at davidferri at iCloud.


Pretty sure you cord is going to be about 1" in diameter in order to carry the 40+ amps need to charge the new EV. RV accessory suppliers have reels that size and some are powered.


Interesting Sense snapshot of the week on EV detection. Two interesting things happening in the EV Device trends screen below.

  1. Sense detects a full Model S programmed charging cycle that starts “underneath” a Model X charging cycle around 1am. Good news - Sense detects the whole S cycle, even with lots of “noise”. Bad News - Still no X detection
  2. Sense detects a Model S manual charging cycle, though only a few minutes of it, not the whole thing, around 5:30pm. Tesla support has gotten back to me and suggested that detecting a manual cycle likely requires additional learning. Good News - Sense detects the start. Bad News - still working on the detecting the real “end of cycle”.

What’s also interesting is that I’m starting to see the “Unknown” component really shrink. If Sense had detected both the X and the remainder of the S manual cycle, my Unknown on this particular and somewhat exceptional day (more car charging than usual) would only be around 20%.


Like this?

Didn’t end up doing it for my Volt, wall works fine with some pegboard hangers. Still waiting for Sense to see my Volt (charging at 220).


Cool! I love the simplicity of the solution, I do have an appreciation for low tech solutions despite being a tech geek.

Before this weekend that would have fit my needs perfectly. However, I found a device called myLift which is a small winch that can be operated remotely via bluetooth. I will be able to install the whole mechanism in the attic above the garage and lower and raise the charging cord at the touch of a button on my iPhone. Everything will be hidden other than the end of the cord hanging through the ceiling. Admittedly, that could have been done with this solution as well, but I’m attracted by the motorized one touch functionality of what I’ve designed. It will take a few weeks to install in my and my son’s spare time and I’ll document as best as I can.