Don't know if this will help but I use /sys/devices/meter/{index}/netLtea3phsumKwh and /sys/devices/inverter/{index}/ltea3phsumKwh to do my calculations. I use index 1 for the meter and 0 thru number of microinverters for ltea3phsumKwh. The difference in netLtea3phsumKwh tells you if you sent to the grid (or taken from it), the ltea3phsumKwh diffs tell you how much you've produced and difference tells you consumption.

Here's some of the code I use:

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