Available from:
Itead.cc
Aliexpress.com
Domadoo.fr
Banggood.com
Amazon.com
Manufacturer:
Sonoff.tech
Install method:
USB to Serial
| GPIO # | Component |
|---|---|
| GPIO00 | Button 1 |
| GPIO01 | None |
| GPIO02 | None |
| GPIO03 | None |
| GPIO04 | None |
| GPIO05 | None |
| GPIO09 | None |
| GPIO10 | None |
| GPIO12 | None |
| GPIO13 | LedLinki |
| GPIO14 | Relay 2 |
| GPIO15 | None |
| GPIO16 | None |
| GPIO17 | None |
| GPIO18 | None |
| GPIO19 | None |
| GPIO20 | None |
| GPIO21 | None |
| GPIO22 | None |
| GPIO23 | None |
| GPIO24 | None |
| GPIO25 | Serial Tx |
| GPIO26 | BL0939 Rx |
| GPIO27 | Relay 1 |
| GPIO6 | None |
| GPIO7 | None |
| GPIO8 | None |
| GPIO11 | None |
| GPIO32 | Switch 1 |
| GPIO33 | Switch 2 |
| GPIO34 | None |
| GPIO35 | None |
| GPIO36 | None |
| GPIO37 | None |
| GPIO38 | None |
| GPIO39 | None |
{"NAME":"Sonoff Dual R3 v2","GPIO":[32,0,0,0,0,0,0,0,0,576,225,0,0,0,0,0,0,0,0,0,0,3200,8128,224,0,0,0,0,160,161,0,0,0,0,0,0],"FLAG":0,"BASE":1}For more accurate energy consumption measurements this device requires power monitoring calibration.
How to identify Sonoff Dual R3 v2
Starting September 2021, Sonoff started to distribute a new version with a different energy monitoring chip (BL0930 instead of CSE7761). There is no functional difference between v1.x and v2. This new model is supported since Tasmota32 v9.5.0.8.
You can identify the v2 from the v1.x by the markings on the PCB and on the energy measurement chip. The photo right below is from Sonoff Dual R3 v2. All Photos on the flashing guide thereafter are from Sonoff Dual R3 v1.6 as there is no difference in the flashing process.
Opening the Case
Press the case to release the clips. My case was not glued at all but some might be. After opening it, the PCB will simply pop out.
Serial Flashing (photos shows Sonoff Dual R3 v1.6)
Disconnect the device from mains power! Like for real!
The four needed pins (3V3, RX, TX and GND) are available at the back of the PCB and can be easily identified.
Connect them to the serial-to-USB adapter. If you have alligator clips or some ingenuity you can do it without soldering, notice that ground is connected to any ground pin on the board, not the marked pad necessarily.
To enter flash mode you need to connect GPIO0 to GND. Luckily Sonoff decided to give you a practical button that does just that.
Download tasmota32.bin (you need v9.3.1.2 and above) or tasmota32-bluetooth.bin if you plan on using the Bluetooth gateway feature.
ESP Flasher
For easiest flash use ESP Flasher. Launch ESP Flasher, select the port for your serial-to-USB adapter and your binary, make sure DUALR3 is in flash mode by pressing down the on board button then connect your serial-to-USB adapter. Finally click “Flash ESP” and wait until complete.
esptool.py
Using command line esptool.py you need to download all the additional required files (**do not right click to download them but click each link and download using the “Download” icon).
Flash using this command line:
esptool.py --chip esp32 --port COM5 --baud 921600 --before default_reset --after hard_reset write_flash -z --flash_mode dout --flash_freq 40m --flash_size detect 0x1000 bootloader_dout_40m.bin 0x8000 partitions.bin 0xe000 boot_app0.bin 0x10000 tasmota32.bin
Configuration
After the flash is complete you will have to connect the DUALR3 to mains and configure Tasmota with webUI using the Wi-Fi AP. ESP32 usually cannot boot properly with power supplied by the serial-to-USB adapter!
Apply the template and make sure “Module 0” is selected. If the power readings are off, perform power monitoring calibration.
Zero Cross Detection Support
To enable Zero Cross Detection use this template
{"NAME":"Sonoff Dual R3 (ZCD)","GPIO":[32,0,0,0,7552,0,0,0,0,576,225,0,0,0,0,0,0,0,0,0,0,7296,7328,224,0,0,0,0,160,161,0,0,0,0,0,0],"FLAG":0,"BASE":1}