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jamesbarnett91 / tplink-energy-monitor

An energy monitoring dashboard for TP-Link smart plugs
GNU General Public License v3.0
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Realtime Usage - Power calculation wrong? #42

Open dalambert5 opened 5 years ago

dalambert5 commented 5 years ago

When consuming only very little I think the power calculation is not correct. At least with the "official" formula P = U x I there should be another result in my example (0.08 A x 228 V = 0 W?) 2019-05-23 22_10_35-Smarte Steckdose - Energy Monitor

tayl commented 5 years ago

This value isn't being calculated by the monitor, it's coming directly from the device. Are the values roughly correct when they're larger?

catalinbordan commented 5 years ago

Hello, I think also, something it is wrong with current reading (A). image 2.21Ax232V=504W. Corect value it is 442W/232V=1.91A No? Thanks

CJcreativeUK commented 5 years ago

I guess it would require some external measurement / calibrated reference loads etc to be sure. I don't have enough information to discount the readings seen by the device.

I will do some load testing using a known - ish load. 1 litre of (room temperature) water in kettle - load approx 3kw - time can be measured.

bowenda commented 4 years ago

Based upon the figures I have recorded today (HS110 firmware 2,0) and your server version 1.5.5 Build 181225 Rel.102720, just installed, Either the total power is out by around 50% but it correlates to the HS110 or the current reading is out by the same amount. It's like there is a large power factor which is ludicrous for my loads. I tend to believe the power reading (other than my comment above re the averages). So 0.36 x 248 should be 91.76W. I suspect the current is in error and should be in the order of 51/248 =0.206A (rounded).

HS110 power error

liakjim commented 4 years ago

Based upon the figures I have recorded today (HS110 firmware 2,0) and your server version 1.5.5 Build 181225 Rel.102720, just installed, Either the total power is out by around 50% but it correlates to the HS110 or the current reading is out by the same amount. It's like there is a large power factor which is ludicrous for my loads. I tend to believe the power reading (other than my comment above re the averages). So 0.36 x 248 should be 91.76W. I suspect the current is in error and should be in the order of 51/248 =0.206A (rounded).

HS110 power error

Most loads ( motors, ac's etc) have as much as 0.5 power factor ( my AC split unit has from 0.5 to 0.99 depending of the load).