Shelly Pro 3EM 400A DIN-Mountable 3-Phase 400A Energy Meter

The Shelly Pro 3EM - 400A is a next-generation DIN rail mountable single or three-phase energy meter, designed for professional-grade monitoring and management of energy consumption across residential, commercial, and industrial installations. Enhanced with Gen2 firmware, LAN connectivity, and 3 x 400A three-phase current transformers, it delivers precision, flexibility, and reliability for integrators and advanced users alike.

This professional-grade energy meter measures accumulated energy as well as real-time values for voltage, current, active and apparent power, and power factor for each phase. It supports 4‑quadrant measurement and multiple wiring configurations, making it suitable for everything from whole-home energy monitoring to complex industrial power distribution systems. With an accuracy class B (IEC 62053‑21) and 1% measurement precision, it provides dependable data you can trust.

Shelly Pro 3EM - 400A stores up to 60 days of 1-minute interval data in non-volatile memory and includes an integrated real-time clock, ensuring timestamps remain accurate even without an internet connection. This device is photovoltaic-ready and can track both imported and exported energy, making it ideal for solar and renewable energy systems.

Designed for seamless integration, it supports LAN, WiFi, and Bluetooth connectivity, and can communicate locally or via the cloud using protocols such as Modbus, MQTT, HTTP, and WebSocket—with all connections secured via TLS. It also features an embedded web interface for direct configuration and monitoring.

External contactor control is available using the Shelly Pro 3EM Switch Add-on, enabling you to automate load control based on real-time data or custom scripts. Please note that the device does not include a built-in relay.

Thanks to its compact DIN rail design and included 400A current transformers, the Shelly Pro 3EM - 400A is easy to install in tight electrical panels, making it ideal for a wide range of applications, including:

• Whole-home or commercial energy monitoring

• Factory and industrial power optimisation

• Data centre or substation monitoring

• Renewable energy installations (solar/wind)

• EV charger and high-load appliance tracking

• Smart grid and building management systems

With its robust hardware, advanced connectivity options, and long-term data logging capabilities, the Shelly Pro 3EM - 400A is the ultimate professional tool for precise energy measurement, intelligent automation, and optimised power management.

Specifications

Power

Power supply voltage AC: 110-240V, 50/60Hz

Power consumption: < 3W

Power metering: 3 channels, up to 400A each

Features

Mounting: DIN rail

Ambient temperature: -20°C to +40°C

Ambient humidity: 30% to 70% RH

Voltmeters (RMS for each phase): 100-260 V

Voltmeters accuracy: ±1%

Ammeters (RMS via CT for each phase and the Neutral): 0-400 A

Ammeters accuracy:

• ±1% at 5-400 A

• ±2% at 0-5 A

Power and energy meter types:

• Active and apparent power

• Active and apparent energy

• Power factor

• Fundamental active and reactive energy

Measurement data storage: At least 60 days of 1 min data resolution

Data export: CSV for PQ recorded values, JSON format export trough RPC

Connectivity

Wi-Fi protocol: 802.11 b/g/n (2.4 GHz)

Operational range (depending on local construction):

• up to 50m outdoors

• up to 30m indoors

Bluetooth protocol: 4.2

CPU: ESP32-D0WDQ6

Flash: 16 MB

Dimensions

(H x W x L): 94 x 19 x 69 mm