First EV devices!



If you guys (gals too) can pull my Voltage logs, I’d be SOOOOO happy…

Tesla programs the cars to sense Voltage, and when it drops too low, it drops the amp draw from 40, to 30. After many inspections and changes/tests in my home. I KNOW the problem lies with how much my power company is providing.
What I need is down to the second resolution on my amp and volt pulls. My EcoBee 3 does this with my HVAC via a website.

I would then be able to let PP&L know that "At 8 PM on xyz, my volts went from 240 to 220 (or whatever) and my car won’t stay at 40 amps. (hence why I’m stuck at 35)…



Matt - still waiting 19 days for my EV to become recognized again on my Sense device. It seems to still be stuck in learning mode even as I charge every day - including today.



I’ll open a ticket with support and let you know what we find.



Hi there,

I have a mid-2015 S85D that Sense detected as an EV on Jan 25th (new device email sent). Unfortunately no consumption has ever registered except for a very brief blip this past Thu (3/16) at 12:45pm EDT - 986w for 2 minutes. This got me very excited for a minute but alas it was not the 20kw I was hoping for! :wink:

After this blip, it has settled back in to the steady state of showing no consumption despite daily charging. The car charges at 80amps (twin chargers with a 100amp circuit running to the HPWC).

@MattAtSense, any ideas? From previous posts on this thread I thought my car was in the supported category. Curious as to what makes this Model S different than the other Model S’s being detected correctly? I’ve been in touch with Support on this and a few other detection issues to no avail.

Help! :slight_smile:



That sounds very frustrating. I’ll file a ticket with support and let you know what we find.



Matt - did you find out anything about my request as well? It looks like the EV learning in my “up next” reset from “almost ready to go” to about half way again. I was excited to see the first mount of data on the first release - now it’s being tempered quite a bit.


Hi Matt,

First, thanks for adding the addition Tesla support. I’m now seeing the same issue as others re only the initial spikes are noticed, not the actual significant draw. I see two start entries (only on live graph) at ~100W each; first at charging initiation, second at point where the additional 40A charger kicks in.

Graph attached of short test.

Any ideas greatly appreciated,

Thanks, Mike



We’re aware of an issue that is causing the monitor to miss certain Tesla charges. This is a different problem than the one I posted about shortly after the first release. I will keep you updated as we learn more.



Not to pile on - just to share… My Sense has a “probe” for EVs in learning mode, but has yet to detect either of my Tesla HPWCs (original ones, not the new smarter ones). Kick-on charging voltage profile looks similar, but not exactly the same (stair step, but with no intermediate “landings”)


Am I correct in assuming that if the Tesla Model S is supported then the same model year Model X is supported as well?


Matt, is there anything we can do to accelerate detection of models not yet recognized, besides charging? My Blink EVSE is a network-connected device.



Based on the data that I have seen, model Xs charge differently. Model Xs are still in progress.




Thank you for asking, but at this point in time we have the data that we need for the most common EVs. The blocking factor is automating the finding of the devices on our end.


[EDIT: slight wording clarification]


@MattAtSense, can you clarify a bit which Model S’s are covered? It sounds like post-refresh models (with the newer 48A/72A chargers that first appeared in the X) are not detected. But it also sounded like early (2012?) are also not detected. Where’s the cutoff? Does single or dual chargers matter (when charging <40A)? Thanks.



A 2012 Tesla that uses a 240V charger should be found if Sense has observed the vehicle for long enough. If you have a 2012 Model S that charges on 240V, and you’ve had Sense installed for a few weeks, but the vehicle still isn’t found, please let me know here / file a support ticket.

You are correct that newer models, including Xs, are still in progress.


PS We’re still working on the issues where Sense doesn’t detect the charge of a car. I’ll post here when we’ve fixed the defect.

[EDIT: grammar]


Hi Matt,
We have both an S and an X on separate 1st gen High Power Wall Chargers (240V). Sense seem to have detected an EV charger precisely once, on March 20th at 2AM, but never again. The S is set for nighttime charging at 2AM Pacific Time, so I suspect that that was a correct detection. But there have been many more chargings since then. BTW-I’m being very specific about chargers since there are now 3 possibilities for 240V charging:

  • Tesla charging cord - comes with every car
  • Tesla High Power Wall Charger (HPWC) - gen 1
  • Tesla High Power Wall Charger (HPWC) - gen 2 - can be daisy chained for smart charging between chargers (I’m sure this feature will cause additional identification challenges).

I can send you more info on the single identification if you need. Let me know.


Matt will correct me if I’m wrong, but charging with the UMC/HPWC (gen1 or 2) shouldn’t matter. Neither of those are chargers, but EVSE’s (EV supply equipment). I’m not just being pedantic; it’s an important point. The charger (in the car) converts AC to DC, and is the source of the load that Sense sees.

The UMC/HPWC is just a glorified relay/extension cord to turn power to the car on or off. It draws slightly over 1W, continuous, and is probably buried in your “Always on” load. The additional load/signature of the relay closing should be imperceptible compared to the load of the charger (it’s around 0.01% of the total charging load).


Understood that the Tesla “chargers” are really just relays with some control logic / interlock included, with all the AC to DC work inside the cars. At the same time, each charger model selects a different peak amperage for a charging session, which I would assume changes the “on signature” for the car.


@kevin1 - If charging at >40A, I’d agree (there’s a definite pause at 40A before the secondary charger comes online), but at 40A or less, I doubt the signature will be different for UMC or HPWC (ie, a single charger car or a HPWC on a 50A breaker).

One thing I haven’t noticed in the graphs posted here - when charging at 24A (on my 14-30) or 30A (in-town Chargepoint), my 2014 P85+ pauses for a second or two at 16A during the ramp up. I’ve only charged at home a couple of times since installing Sense, so I’m not concerned that it hasn’t been detected (yet).


Ummm…ETA on the Nissan Leaf detector?