Shelly Pro 3EM-400 is a three-phase energy meter designed for DIN rail mounting. Equipped with the full flexibility of gen2 firmware and LAN connectivity, it offers professional integrators additional options for end-user solutions. It can operate independently within a local LAN and/or Wi-Fi network or can be used through cloud home automation services via MQTT, HTTP, and WebSocket. All incoming connections support TLS. The device reports cumulative energy as well as instantaneous voltage, current, real power, and apparent power per phase in real-time. It stores data in non-volatile memory, which can be retrieved for up to 60 days in 1-minute intervals. The device features a real-time clock to maintain the correct time even when the connection to an SNTP server is interrupted. Users can remotely access, set up, and monitor the Shelly Pro 3EM-400. Additionally, the device can access and communicate with an automation system as long as it is within the same network infrastructure. It includes a built-in web interface that allows you to monitor and control the device as well as adjust its settings. The device does not have a built-in relay. Control of the contactor is done through a Shelly Pro add-on connected to the Shelly Pro 3EM-400.