Sonoff S40 Smart Plug

The Sonoff S40 Smart Plug is a compact WiFi outlet adapter with energy monitoring capabilities in a small form factor designed for tight spaces. The plug features real-time power consumption tracking and supports loads up to 15A, making it suitable for most household applications. The slim profile reduces interference with adjacent outlets compared to bulkier smart plugs.

This plug includes overload and over-temperature protection for safety, automatically cutting power if dangerous conditions are detected. The eWeLink app provides scheduling, timers, power consumption history, and scene automation. Power-on state is configurable to suit different use cases, from always-on for critical devices to always-off for safety.

The S40 integrates with Amazon Alexa and Google Home through eWeLink cloud services, enabling voice control and routine integration. Home Assistant users can integrate the plug through multiple methods including the official eWeLink integration or custom firmware. The affordable price point and energy monitoring make it particularly useful for tracking consumption of specific appliances.