Shelly Pro 3EM 120A, Current transformer, Energy meter

Shelly Pro 3EM – professional energy meter for DIN rail

Shelly Pro 3EM is an advanced device of the new generation that redefines the way you manage resources in your building. This three-phase meter, which you will find in our shop, is designed for DIN rail mounting, making it easy to integrate into professional electrical distribution boards. With support for loads of up to 120A, Shelly Pro allows precise monitoring of how much energy is consumed by individual circuits or entire office and industrial facilities. It is a professional, industrial-grade module that combines reliability with the remarkable ease of use known from IoT systems.

Reliable Wi-Fi, LAN and Bluetooth connectivity in the Shelly Pro series

The key advantage of Shelly Pro 3EM is its triple communication standard: Wi-Fi, LAN and Bluetooth. Thanks to the LAN connection, the device ensures the highest stability of data transmission, which is crucial in places with a high density of radio waves or where wireless networks do not reach. The ability to quickly connect the 3EM to local infrastructure means that control over power parameters is available in real time. What is more, Shelly Pro 3EM can operate autonomously or as part of a larger network, using HTTP and MQTT protocols to communicate with other automation systems.

Precise 120A current transformer and current measurement

The set includes three high-quality CT transformers, which allow non-invasive current measurement on each of the three phases. Each current transformer with a capacity of 120A has an openable core, so installation does not require cutting the wires – simply clamp it around the phase cable. This solution makes measurement safe and quick to carry out. The highly sensitive transformer guarantees 99% accuracy in active energy measurement, allowing you to precisely track how current flows in your installation and identify devices generating the highest costs.

Monitoring active energy and control of the three-phase network

Shelly Pro 3EM is not only a consumption meter, but also a device monitoring voltage parameters and network quality. The module can calculate bidirectional consumption, making it an ideal choice for photovoltaic system owners – you can check how much energy you feed into the grid and how much you draw from it. In addition, the 3EM enables current measurement on the neutral wire (using an optional fourth CT), which allows you to detect possible leakage or load imbalance. It is a comprehensive tool that makes your smart home safer and more energy-efficient.

Shelly Pro 3EM and an advanced relay in your Smart Home

It is worth noting that Shelly Pro 3EM has been equipped with an integrated output relay rated up to 2A. It allows direct control of an external contactor, enabling automatic disconnection of the load after exceeding defined voltage or power limits. As a result, shelly pro 3em becomes an active guardian of the installation, rather than just a passive meter. All information is collected and available as a data history for up to 60 days directly in the device memory, allowing in-depth analysis without the need for a constant cloud connection. It is true monitoring power enclosed in a DIN rail housing.

Technical data

Key advantages

• Highest precision of active energy measurement (99%) with industrial-grade certification.
• Triple connectivity (LAN, Wi-Fi, Bluetooth) guaranteeing reliable access to data.
• Three openable 120A transformers included for non-invasive installation.
• Bidirectional measurement – ideal for monitoring production from photovoltaic panels.
• Built-in relay enabling automatic response to events in the network.

The product is intended for

• Homeowners with photovoltaic installations who want to monitor self-consumption.
• Office building managers looking for a stable DIN rail meter with LAN connectivity.
• Smart Home system installers requiring accurate data on current and voltage.
• Industrial companies aiming to optimise energy costs and protect machinery.