I am also facing similar situation.
I was perviously using wifi connection to Huwaei inverter itself, which was reading correctly without any abnormal spike readings. Only issue was weak wifi signals of inverter which lead to missing/gaps in reading.
Since I updated my dongle’s firmware to read from wifi dongle’s wifi (which is more stable without any dropouts). I am facing abnormal spikes in hundreds
It can happen with any of the three values.
All three have state_class:total_increasing increasing.