How to read the exported CSV file

  • Hi, I am having trouble reading the CSV file exported from the web interface of the Shelly 3EM smart meter. First of all, how do I calculate energy consumption for one day? I converted the .csv to .xlsx but for some days I saw readings of the consumption for each minute of the day but for other days the readings are for 10 minutes period. Also some of the days are not in the chronological order which is very strange. I don't understand how the energy for one reading is calculated, because some of the values are bigger than what I expect. I saw for example 40 kWh at one moment of the day, but even if I power on all my consumers in the house in the same time I will not come even closer of half of that number. My maxim approved power for the house is 9kW three-phase installation. I attached my latest csv file if someone wants to take a look and advice me. Their support couldn't articulate a clear answer on this :(. Thanks in advance!

  • I haven't a 3em so I have to ask, is this for only one of the 3 measuring?


    When I look at your csv end I can see this

    Code
    2021-04-28 23:56,5.70,0.00
    2021-04-28 23:57,5.81,0.00
    2021-04-28 23:58,6.09,0.00
    2021-04-28 23:59,6.09,0.00

    first, I think there was a changing because between the 20 and 28 is nothing and now is every minute an entry.

    The second what I can see you have in this 4 minutes a usage from 23,69 Watt


    As example from my dimmer (safe every hour)

    Code
    "2021-04-30 18:00:00","0.41"
    "2021-04-30 19:00:00","10.93"
    "2021-04-30 20:00:00","0.26"

    And this are watts.

  • The file shows the total consumption for all three phases. The inputs are not consistent and I don't know if I can count on these readings.

  • Hello


    From my understanding you can simply add up the values for one day - if you want the actual value for one time period of 10 minutes you have to multiply the value with 6.

    I use the Shelly 3EM for my wallbox and the values fit to the car settings - For a EXCEL with German settings it is just necessary to replace the value-dots by kommas.


    My problem is that the time of the recordings seems to be not accurate. I have recordings from my PV and there is a time shift of app. 2h. I checke the Shelly time setting with is ok - I have bo idea on that point.

  • The times are all UTC for the downloaded data. The times from the app are your local time. If you want to know the consumption in Watts for a given period, just add them. However, there is --in my case, small error. I have compared my old Eyedro with my new EM3 against the daily meter reading at midnight. This is what I got so far:


    Date Meter @23:55 Eyedro Eyedro Error Shelly EM3 Shelly EM3 Error
    kW.h kW.h kW.h % kW.h %
    31-May 79727 28.18
    1-Jun 79753 26 24.94 -4%
    2-Jun 79785 32 30.55 -5%
    3-Jun 79813 28 34.71 24% 26.88 -4%
    4-Jun 79838 25 33.71 35% 24.19 -3%
    5-Jun 79862 24 34.17 42% 22.44 -6%
    6-Jun 79888 26 35.77 38% 25.08 -4%
    7-Jun 79917 29 35.04 21% 27.28 -6%
    8-Jun 79954 37 40.85 10% 36.04 -3%
    9-Jun 79979 25 34.10 36% 23.93 -4%
    10-Jun 80007 28 38.19 36% 26.3 -6%
    11-Jun 80035 28 37.54 34% 27.52 -2%
    12-Jun 80060 25 36.13 45% 24.19 -3%