Sonoff are dirt cheap WiFi AC/DC relay systems based on ESP8266 selling for about $5 with board and case. They are made by ITEAD Studio, and the company has now new versions supporting up to 16A @ 250V, and with a 2.5mm connector to connect external temperature and humidity probes.
- SoC – Espressif ESP8266 Tensila L106 32-bit MCU up to 80/160 MHz with WiFi
- Connectivity – 802.11 b/g/n WiFi with WPA/WPA2 support
- Terminals – 6 terminal for mains and load’s ground, live and neutral signals.
- Misc – 4-pin 2.5mm jack for external probes, LEDs for power and WiFi status
- Dimensions – PCB: 89.1 x 45.0 x 1.2mm
- Temperature range – -40 ℃ to 125 ℃
The company also offer two probes to connect the sensor jack: one based on AM2301 sensor for temperature (-40 to +80 °C, +/- 0.5 °C) and humidity (10 to 90%, +/- 3%), and an a waterproof temperature probe based on DS18B20 supporting -55 to 125 °C range.
ITEAD Studio now have a nice portfolio of inexpensive device for “smart home”. Please note that (AFAIK) none of the items have UL or TUV safety certifications, so use them at your own risks.
Thank to Harley for the tip.
Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.