The Shelly Pro 3EM is a DIN rail-mounted three-phase energy meter designed for monitoring electrical energy consumption and production in residential, multi-apartment, commercial, and light industrial environments. While its core measurement capabilities remain unchanged from the previous model, it introduces native Modbus support, up to 60 days of local data storage, an enhanced firmware platform, and mTLS security support, making integration into industrial and building automation systems even easier. The device uses current transformers (CTs), allowing current measurement without interrupting the electrical circuit.
The meter monitors three phases with a measurement range of up to 120 A per phase and optionally supports neutral conductor current measurement. It supports four-quadrant measurement, making it suitable not only for energy consumption monitoring but also for measuring generated energy, such as tracking energy flow in photovoltaic systems.
The Shelly Pro 3EM features Ethernet, Wi-Fi, and Bluetooth connectivity. It includes a built-in web interface together with MQTT, HTTP, WebSocket, and scripting support. The device stores at least 60 days of measurement data locally with 1-minute resolution.
Please note that the Shelly Pro 3EM does not include a built-in relay. External contactor control requires the Shelly Pro 3EM Switch Add-on, which is available separately. Matter upgradable - Available after updating to latest firmware.
About Shelly
Shelly develops smart home and building automation devices with a strong focus on local control, open integrations, and advanced energy monitoring. The Shelly Pro series consists of DIN rail-mounted products designed for professional applications.
Shelly devices typically support a local web interface, MQTT, HTTP API, WebSocket communication, scripting, and integration with numerous smart home platforms.
Typical Applications of the Shelly Pro 3EM 120A V2
Industrial Equipment
The Shelly Pro 3EM supports Modbus communication for voltage, current, power, and energy measurements. It accurately samples energy consumption together with real-time voltage, current, and power values. The latest firmware generation also enables custom integrations, allowing the device to report energy data to external infrastructure as frequently as every 100 ms.
Bidirectional Energy Monitoring
Monitor your home, office, or industrial facility to avoid unnecessary costs and voltage drops that could damage equipment. The Shelly Pro 3EM measures bidirectional energy flow, tracking both consumed and generated energy across all three phases. It can also be configured to monitor three independent circuits within a single-phase electrical installation. The device provides insight into electrical network quality by measuring active power, reactive power, voltage, and power factor.
Local Automation
Using the Shelly Pro 3EM's scripting engine and webhooks, you can easily control other Shelly devices or Wi-Fi devices on the local network. This allows precise control of heating, cooling, or electric vehicle charging based on photovoltaic production, enabling connected devices to automatically adjust their energy consumption. All of this operates entirely without cloud services.
Photovoltaic System Monitoring and Control
Monitor the energy produced by your solar panels or wind turbines with ease. The Shelly Pro 3EM provides real-time information about the performance of renewable energy systems together with historical production and consumption data recorded every minute for up to 60 days. This helps optimize energy flow and maximize the efficiency of photovoltaic and wind energy systems. When combined with other Shelly devices, custom scenes can automatically perform actions such as switching loads or triggering alarms.
For Developers
The Shelly Pro 3EM can be integrated with most home automation platforms using its factory firmware.
The official REST API documentation is available from the manufacturer at:
http://shelly-api-docs.shelly.cloud/
Additional supported platforms and integrations:
- MQTT
- HomeSeer
- ioBroker
- Home Assistant
- openHAB
- Domoticz
- SYMCAN
- nymea
- Hubitat
- HOOBS (Homebridge out of the box)
- REST API
Key Product Features
- Three-phase energy measurement: Measures energy consumption and production on three phases.
- Current transformer measurement: Supports CT measurement up to 120 A per phase.
- Four-quadrant measurement: Suitable for measuring both energy consumption and energy export.
- Suitable for photovoltaic systems: Ideal for monitoring solar energy generation.
- At least 60 days of local data storage: Stores measurement data with 1-minute resolution in non-volatile memory.
- Ethernet and Wi-Fi connectivity: Supports both wired and wireless networking.
- Built-in web interface: Browser-based configuration and monitoring.
- Phase sequence error detection: Optional detection of incorrect phase rotation.
- Real-time clock: Maintains accurate timestamps even during internet outages.
- Optical pulse indication: LED indication of energy flow.
- No built-in relay: External contactor control requires the Shelly Pro 3EM Switch Add-on.
Measurement Functions
- Per-phase RMS voltage measurement.
- Per-phase RMS current measurement, with optional neutral conductor measurement.
- Active power measurement.
- Apparent power measurement.
- Active energy measurement.
- Apparent energy measurement.
- Fundamental active and reactive energy measurement.
- Power factor measurement.
- Phase sequence error detection.
- Channel-to-channel calibration.
- No-load threshold function below 30 VA per channel.
- CSV export for recorded power quality values.
- JSON data access via RPC.
Smart Home Protocols and Platform Compatibility
- Ethernet: RJ45 wired network connection.
- Wi-Fi: 2.4 GHz wireless connectivity.
- Bluetooth: Used for commissioning and local communication.
- Matter-ready: Can become Matter-compatible via future firmware updates.
- MQTT: Suitable for local or server-based automation systems.
- HTTP API: Documented local control and data access.
- WebSocket: Real-time communication.
- TLS support: Incoming connections are secured with TLS.
- Shelly Smart Control: Full monitoring and configuration using the official app.
- Home Assistant: Supports local integration.
- Node-RED and openHAB: Integration via MQTT or HTTP API.
- LAN mode: Full local operation without cloud services.
- Cloud mode: Remote access through Shelly Cloud.
- Matter upgradable: Available after updating to latest firmware
Smart Features
- Real-time energy monitoring.
- Three-phase load balancing monitoring.
- Solar production and grid import/export monitoring.
- Peak consumption analysis.
- Abnormal consumption pattern detection.
- Local automations using scripting.
- Webhook-based event notifications.
- MQTT data publishing.
- Remote monitoring via Shelly Cloud.
- Local operation without an internet connection.
- External contactor control using the Shelly Pro 3EM Switch Add-on.
Technical Specifications
- Product name: Shelly Pro 3EM
- Model: SPEM-003CEBEU
- Type: DIN rail-mounted three-phase energy meter
- Dimensions: 94 × 19 × 69 mm
- Weight: 62 g
- Enclosure material: Plastic
- Colour: White
- Mounting: DIN rail
- Terminal screw torque: 0.4 Nm
- Wire cross-section: 0.5–2.5 mm²
- Wire stripping length: 6–7 mm
- Operating temperature: -20 °C to +40 °C
- Humidity: 30–70% RH
- Maximum installation altitude: 2000 m
- Power supply: 100–260 V AC, 50/60 Hz
- DC power supply: Not supported
- Power consumption: < 3 W
- External protection: B or C curve circuit breaker, maximum 16 A rated current, minimum 6 kA breaking capacity
- Voltage measurement range: 100–260 V RMS per phase
- Voltage measurement accuracy: ±1%
- Current measurement range: 0–120 A per phase and neutral conductor
- Compatible current transformer: CT 120 A
- Current measurement accuracy: ±1% between 2–120 A, ±2% between 1–2 A, ±5% between 0–1 A
- Active energy accuracy class: Class B
- Included current transformers: 3 × 120 A CT
- Data storage: At least 45 days with 1-minute resolution
- Data export: CSV and JSON via RPC
- No-load threshold: 30 VA per channel
- Minimum calibration load: 500 W per channel
- Internal temperature sensor: Yes
- Ethernet: 1 × RJ45 port
- Wi-Fi protocol: IEEE 802.11 b/g/n
- Wi-Fi range: Up to 30 m indoors, up to 50 m outdoors
- Bluetooth protocol: Bluetooth 4.2
- Bluetooth range: Up to 10 m indoors, up to 30 m outdoors
- RF band: 2400–2495 MHz
- Maximum RF output power: < 20 dBm
- CPU: ESP32-D0WDQ6
- Flash memory: 16 MB
- Webhooks: 20 webhooks, up to 5 URLs per webhook
- Scripting: Yes
- MQTT: Yes
- CoAP: No
- Built-in relay: No
- External contactor control: Via Shelly Pro 3EM Switch Add-on
