Smart WiFi plugs (TP-Link Kasa, Gosund, Shelly) use internal PCB connectors to link the ESP8266/ESP32 Wi-Fi module to the relay, current sensing circuit, and AC power supply within the plug housing.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | VCC | 3.3V MCU supply | PWR |
| 2 | GND | Ground | GND |
| 3 | RELAY | Relay control GPIO | I/O |
| 4 | CF | Current measurement pulse CF | ADC |
| 5 | CF1 | Current or voltage measurement | ADC |
| 6 | LED | Status LED control | I/O |