Negative wattage with always on devices and no solar

Hi All,
I had Sense for roughly 6 months and I love it. I recently noticed that, once only “always on” devices are on, lug #1 reports negative wattage. See snapshot below. It is not much.
I have no solar and clamps are installed facing feeder.
Any idea? Maybe it is just a calibration issue.
Thank you!

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It sure sounds like a reversed CT.
Got a photo by any chance?

Thanks! Admittedly I don’t have a picture handy now but I can take one. Interestingly enough, the negative reading happens only when everything is off (except the “always on” devices). See for instance a snapshot of my current consumption:

You are using MORE energy when everything is off ?
Are by any chance the CT’s switched around?
L1 & L2 got switched ?
I think it is best to open a case with support@sense.com
They can see a lot more than we (the customers) can.
Please let us (me!!) know what comes out of this!
Something is “different” about this :wink:

I have a similar problem that started just over 24 hours ago. Everything was fine until 9 am when the solar trace reverted to zero and I get negative readings on mains until sundown, and then I get visible usage. I have only had sense for about two weeks, as part of beta trial here in Australia. When first installed this is exactly what happened; I only saw signal on usage when it exceeded the solar generation. Seems a setting at Sense HQ has reverted - but why? Nothing has changed in my meter box. I really hope this is not a regular occurrence because the only likely solution is to submit a support ticket. I have done that on this occasion but it’s not a good time of year for getting tech support.


This has been going on for years and is a known “issue” that Sense either isn’t able or doesn’t want to fix.
In the USA there are 2 ways you can hook up solar to a meter setup:

Load side vs Line or Supply-side
See How to connect a PV solar system to the utility grid

Once you have hooked up your CT’s for your situation, the Sense Algorithm seems to be able to “detect” what is used.
For years suddenly the config, while neither customer not support, does ANYTHING somehow tries again and should be reversed. This new setting leads to what you are seeing.

Contact support, give them a link to this thread.
They will know what to do and things should go back to normal.
Until it happens again. I had it happen to my system 3 times!
Best of luck!