Reply To: I opened the cheap Wi-Fi plug: what are the signals between the logic board and the power board?

It was the BL0937, I was using SEL the wrong way round, I was reading current and voltage swapped, it thought 230 V was 0.8 A 🙂 I calibrated it with a 100 W heater, and it reads 59.2 W on the 60 W bulb plugged into the socket. I don’t plug it in at all while programming now, I set up OTA. Thanks Oğuz.