Kasa Smart Plug on Plug n Play solar outlet; Reverse energy direction?

I don’t think this is a Sense bug – maybe a Kasa Smart Plug bug? – but it’s a strange case I thought I’d report.

I have a plug-n-play solar panel on the roof (as mentioned in Will sense work with the Legion solar 2 (puts energy into your lines)… note to @agregg18: it’s smart enough to stop producing if the grid is down).

I recently added a Kasa smart plug to monitor the panel output, so now it shows up nicely in my Sense display:

…and thanks to Sense & Kasa I now have a nice log of the panel’s output:

All good! The only problem is that the energy measurement is reversed. Perhaps the Kasa smart plug reports the absolute value of the energy flow, showing consumption of 187 watts when it is actually producing 187 watts.

I checked the device settings in Sense to see if there were some way to reverse the reading from the smart plug, but didn’t see it.

Not a big deal, but any suggestions?

I believe this is the answer here, but I’d be curious as to what TP-Link/Kasa support says.
I need to look into this further, but I believe you would need to monitor production and consumption through separate sensors (as with Sense Solar) in order to get that distinction within the app. All Sense can see is the power coming through the mains, not at the breaker-level, so my gut is telling me that a plug-and-play solution still wouldn’t work here as intended.

You are correct, this is not a feature in the app at this time.

What is the value shown in the Kasa app?

There’s a person here who wrote an integration to emulate Kasa smartplugs so that other data sources could be force-fed into Sense. Maybe they could tell us what datatype is associated with that power value? If it’s an unsigned integer, well, there’s our answer.

Not sure there’s a bug in any device. With AC current / voltage and no reference to the grid, there’s no easy way to designate polarity. I think when Sense does its solar calibration, the monitor establishes the power reference for positive and negative energy flow. But if you are just measuring the waveforms, you have no way to know the direction of energy flow.

Saw your post, so I gave it a try! For what it’s worth the TP Link protocol is just JSON, so I don’t think there’s even an unsigned number type anyway.

I configured a static SenseLink plug to -15W and while Sense does detect it as a new device, it reports the plug as off*. So it would appear you can’t currently report a negative/power-production value via a smart plug to Sense.

*In terms of power reading, at least. It shows the switch control status as “on”, but I haven’t gotten around to implementing the switch control from Sense function in SenseLink.

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