Shelly is a premier brand of smart home automation products manufactured by Allterco Robotics (now operating under Shelly Group AD). Unlike traditional smart home brands that require completely replacing your existing wall switches, light fixtures, or outlets with bulky proprietary hardware, Shelly specialized in creating extremely compact, retrofit smart relays and sensors.
These tiny modules are designed to fit discreetly inside standard European wall junction boxes (such as standard French flush-mounting boxes / boîtes de encastrement), behind existing light switches, socket outlets, or inside electrical panels. When installed, Shelly devices turn traditional “dumb” electrical appliances and lighting circuits into fully automated, connected smart systems while keeping your existing wall switches and decor entirely intact.
What sets Shelly apart in the modern smart home market—especially across France and Europe—is its unique local-first philosophy. While most consumer smart home brands lock users into proprietary cloud ecosystems, Shelly devices come out-of-the-box with built-in web servers, open APIs, local HTTP REST control, MQTT protocol support, and native integration capabilities with local hubs like Home Assistant. You get full control over whether your devices communicate through the cloud or operate strictly within your local Wi-Fi network.
Shelly Overview
Shelly Group AD (formerly Allterco AD) is a European technology leader headquartered in Sofia, Bulgaria, with regional hubs across Europe (including dedicated distribution channels for France at [shelly.com/fr](https://shelly.com/fr)) and North America. Founded with a vision to democratize home automation, the company quickly transitioned from telecommunications services into one of Europe’s fastest-growing IoT (Internet of Things) hardware manufacturers.
Smart Home Products Offered by Shelly
Shelly’s product catalog spans multiple generations and series tailored for basic home users, advanced DIYers, and professional electrical installations.
┌─────────────────────────────────────────┐
│ Shelly Product Ecosystem │
└────────────────────┬────────────────────┘
│
┌──────────────────┬──────────┴─────────┬──────────────────┐
▼ ▼ ▼ ▼
┌──────────────┐ ┌──────────────┐ ┌──────────────┐ ┌──────────────┐
│ Relays & │ │ Energy │ ┌ BLU Series │ │ Pro & Wave │
│ Controllers │ │ Meters │ │ (Bluetooth) │ │ (Professional│
└──────────────┘ └──────────────┘ └──────────────┘ └──────────────┘
1. Retrofit Smart Relays (Plus & Gen 3 Series)
-
Shelly 1 / Shelly Plus 1: A single-channel dry-contact switch capable of controlling up to 16A loads. Ideal for lights, garage doors, gates, and low-voltage applications.
-
Shelly 1PM / Plus 1PM / Gen 3 1PM: Adds precise power metering (PM) capabilities to monitor real-time power consumption and historical energy usage up to 16A.
-
Shelly 2PM / Plus 2PM: Dual-channel smart relay with power measurement, widely used for controlling dual lighting circuits or motorized roller shutters (volets roulants) with position control.
-
Shelly Dimmer 2 / Gen 3 Dimmer: Allows smooth dimming of halogen, trailing-edge LED, and dimmable electronic transformers without requiring a neutral wire in many wiring configurations.
2. Shelly BLU Series (Bluetooth Low Energy)
-
Shelly BLU Door/Window: Compact battery-powered sensor tracking open/close states, tilt angle, and light intensity (lux).
-
Shelly BLU Motion: High-speed motion sensor with integrated light sensor and ultra-long battery life (up to 5 years).
-
Shelly BLU Button1: Portable Bluetooth action button to trigger custom automation scenes around the house.
3. Professional DIN-Rail Series (Shelly Pro Line)
-
Designed for mounting on standard DIN rails inside main breaker panels and distribution boards.
-
Features integrated RJ45 Ethernet ports for ultra-reliable wired network communication alongside Wi-Fi and Bluetooth.
-
Equipped with flame-retardant enclosures (V-0 rated) and advanced thermal protection.
4. Energy Monitoring Solutions (Shelly EM & 3EM Series)
-
Shelly EM: Dual-clamp current transformer (CT) energy meter for single-phase systems.
-
Shelly Pro 3EM / 3EM: High-precision 3-phase energy meter capable of real-time monitoring of solar panel production (grid export) vs. home energy consumption.
5. Smart Plugs & Bulbs
-
Shelly Plus Plug S / Plug US: Plug-and-play smart plugs with customizable RGB LED indicator rings, load monitoring, and over-power safety cutoffs.
-
Shelly DUO & Vintage Bulbs: Smart Wi-Fi LED bulbs offering dimmable warm-to-cool white light without requiring a bridge.
Key Features of Shelly Explained
Shelly devices stand out from competitors due to several core engineering principles embedded into every product:
┌─────────────────────────────────────────────────────────────────┐
│ Key Shelly Engineering Pillars │
├────────────────────────────────┬────────────────────────────────┤
│ 1. No Hub Required (Wi-Fi/BLE) │ Direct connection to 2.4GHz │
├────────────────────────────────┼────────────────────────────────┤
│ 2. Compact Retrofit Design │ Fits inside wall sockets/boxes │
├────────────────────────────────┼────────────────────────────────┤
│ 3. Local Web Server Built-In │ Control via internal IP address│
├────────────────────────────────┼────────────────────────────────┤
│ 4. Open APIs (MQTT/HTTP/CoAP) │ Zero cloud lock-in │
├────────────────────────────────┼────────────────────────────────┤
│ 5. Advanced Scripting (mJS) │ Custom local logic on device │
└────────────────────────────────┴───────────────────────────────┘
-
No Hub Required: Every Wi-Fi device connects directly to your standard 2.4 GHz Wi-Fi router. You don’t need to buy a proprietary £50–€100 bridge or hub to start out.
-
Built-in Web Server: Each Shelly device hosts its own embedded web interface accessed via its IP address in any browser. You can configure network settings, update firmware, and manage schedules offline.
-
Local Scripting (mJS): Shelly Plus and Gen 3 devices support micro-JavaScript (mJS) running directly on the hardware ESP32 chip. This means complex conditional automations execute locally even if your internet connection goes down.
-
Dry Contact Support: Select relays (like Shelly Plus 1) offer dry (potential-free) contacts, meaning the control circuit power supply is isolated from the switched load voltage. This allows triggering 12V DC garage motors using a 230V AC mains powered relay.
-
Bluetooth Gateway Functionality: Wi-Fi-powered Shelly Plus/Gen 3 devices act as Bluetooth gateways, listening for signals from battery-operated Shelly BLU sensors and passing them to your network.
Shelly Cloud & Mobile App
While Shelly devices do not strictly require a cloud connection, the Shelly Smart Control app (available on iOS, Android, and web browser) provides a polished interface for everyday users who want remote access and visual organization.
┌─────────────────────────────────────────────────────────────┐
│ Shelly Smart Control App │
├──────────────────────────────┬──────────────────────────────┤
│ Custom Dashboard │ Room-by-room organization │
├──────────────────────────────┼──────────────────────────────┤
│ Energy Analytics │ kWh graphs, cost estimating │
├──────────────────────────────┼──────────────────────────────┤
│ Cloud & Web Scenes │ Multi-device triggers & time │
├──────────────────────────────┼──────────────────────────────┤
│ Remote Access │ Control home from anywhere │
└──────────────────────────────┴──────────────────────────────┘
-
Dashboard Customization: Organize your home into rooms, floors, and custom widgets.
-
Energy Management Dashboards: Detailed charts show historical kilowatt-hour (kWh) usage, peak power draws, and estimated electricity bills over daily, weekly, or yearly intervals.
-
Automations & Scenes: Create time-based schedules, sunset/sunrise triggers, or multi-device scenes (e.g., “Good Night” turning off all lights and lowering roller blinds).
-
Optional Cloud Sync: Cloud connectivity is completely optional. You can toggle cloud sync off per individual device for enhanced privacy while maintaining local network access.
Installation & Setup Process
Installing a Shelly smart relay involves electrical wiring behind existing wall fixtures, making it a simple job for competent DIYers or certified electricians.
Smart Home Compatibility
Shelly provides exceptionally broad multi-platform integration across the entire smart home market.
┌──────────────────┐
│ Shelly Relay │
└────────┬─────────┘
│
┌──────────────┬────────────────┼────────────────┬──────────────┐
▼ ▼ ▼ ▼ ▼
┌────────┐ ┌────────────┐ ┌───────────┐ ┌───────────┐ ┌──────────┐
│ Amazon │ │ Google │ │ Apple │ │ Home │ │ Matter │
│ Alexa │ │ Assistant │ │ HomeKit │ │ Assistant │ │ Protocol │
└────────┘ └────────────┘ └───────────┘ └───────────┘ └──────────┘
-
Amazon Alexa & Google Home: Enables voice commands (“Alexa, turn on the living room lights”) via official cloud skills.
-
Apple HomeKit: While native HomeKit support was historically limited, newer Shelly Gen 3 / Matter-enabled firmware and custom open-source HomeKit firmware allow direct pairing with Apple Home without third-party bridges.
-
Home Assistant: Shelly is widely regarded as the best consumer hardware for Home Assistant. The native integration auto-discovers Shelly devices over the local network using CoAP/mDNS, offering instantaneous control without cloud dependency.
-
Matter Support: Gen 3 and modern Shelly Plus devices support Matter over Wi-Fi, allowing them to communicate natively with Apple Home, SmartThings, Google Home, and Alexa over a unified protocol.
Energy Monitoring & Automation Features
Energy efficiency is one of the primary drivers for buying Shelly products, especially in European markets experiencing rising utility costs.
┌─────────────────────────────────────────────────────────────┐
│ Shelly Energy & Automation Toolkit │
├──────────────────────────┬──────────────────────────────────┤
│ Solar Auto-Consumption │ Route excess solar power to │
│ │ heat pumps or water heaters │
├──────────────────────────┼──────────────────────────────────┤
│ Over-Power Protection │ Automatically disconnects loads │
│ │ exceeding safety limits │
├──────────────────────────┼──────────────────────────────────┤
│ Schedules & Webhooks │ Trigger local HTTP REST commands │
│ │ between devices without a hub │
└──────────────────────────┴──────────────────────────────────┘
-
Real-time Consumption Tracking: Monitor active voltage (V), current (A), power factor (PF), and instantaneous watts (W).
-
Automated Load Shedding: Configure local scripts on devices like the Shelly Pro 3EM to turn off non-essential appliances (e.g., EV chargers or pool pumps) when total home power consumption approaches breaker thresholds.
-
Solar Integration: Pair a Shelly EM or Pro 3EM at your main meter to detect net energy export. Use local webhooks to automatically turn on heavy loads (boilers, air conditioning) when solar panels generate excess electricity.
Shelly Pricing Overview
Shelly products are globally acclaimed for offering unmatched value per euro compared to traditional smart home brands.
Pros & Cons
Pros
-
Extremely Competitive Pricing: Top-grade hardware starting at under €15 per relay.
-
No Vendor Lock-in / Local First: Native MQTT, REST HTTP APIs, and local web servers built-in.
-
Fits Existing Electrical Infrastructure: Keeps original switch plates, wall sockets, and interior aesthetics intact.
-
Outstanding Home Assistant Integration: Instant auto-discovery and zero cloud latency.
-
Extensive Product Range: Covers everything from single-channel relays to 3-phase DIN-rail energy meters.
Cons
-
Requires Electrical Wiring Knowledge: Installation involves working with mains voltage behind switch plates.
-
Neutral Wire Preferred: While products like Shelly Dimmer 2 work without neutral, most core relay switches require a neutral wire in the wall box.
-
Tight Wall Boxes: Older shallow flush-mounting boxes (30mm depth) can be crowded when placing wires and relays together.
User Experience
From an everyday user perspective, Shelly provides a dual-layer experience:
-
For Non-Technical Household Members: Nothing changes physically. Flipping the wall light switch still turns the light on and off instantly without lag, even if the Wi-Fi router is offline.
-
For Smart Home Enthusiasts: It delivers an unmatched sandbox. Responsiveness over local Wi-Fi or MQTT is virtually instantaneous (under 50ms latency), and automations run reliably without relying on third-party cloud servers.
Safety, Security & Privacy
Shelly takes safety and data privacy seriously, designing devices to meet strict European electrical regulations.
-
Overheating & Overcurrent Protection: Internal thermal sensors shut off power automatically if internal temperatures or electrical loads exceed safe parameters.
-
Flame-Retardant Materials: Enclosures are manufactured using V-0 rated fire-resistant materials.
-
Local Security Controls: You can password-protect local web interfaces, disable the broadcasted Wi-Fi access point, and turn off cloud connectivity completely to eliminate remote attack vectors.
-
GDPR Compliance: For users opting into Shelly Cloud, servers hosted within the European Union comply fully with GDPR privacy guidelines.
Shelly vs Competitors
To understand where Shelly fits in the wider smart home market, let’s compare it against other leading smart device brands:
Who Should Use Shelly?
┌─────────────────────────────────────────────────────────────┐
│ Target User Profiles │
├──────────────────────────────┬──────────────────────────────┤
│ DIY Smart Home Builders │ Native Home Assistant/MQTT │
├──────────────────────────────┼──────────────────────────────┤
│ Energy-Conscious Homeowners │ Granular solar/kWh analytics │
├──────────────────────────────┼──────────────────────────────┤
│ Renovators & Electricians │ Retrofit into existing boxes │
├──────────────────────────────┼──────────────────────────────┤
│ Privacy-Focused Users │ 100% offline local control │
└──────────────────────────────┴──────────────────────────────┘
-
DIY Home Automators: Anyone building a Home Assistant, openHAB, or custom MQTT ecosystem.
-
Privacy Advocates: Homeowners who refuse to let cloud servers log when they enter a room or flip a light switch.
-
Solar & Energy Management Enthusiasts: Users wanting to optimize electricity consumption and track solar production in real time.
-
Renovators Wanting to Keep Existing Fixtures: People who love their decorative designer wall switches and don’t want cheap plastic smart switches taking over their walls.
Expert Verdict
Shelly has set the standard for retrofit home automation. By prioritizing open standards, local control, robust hardware engineering, and affordable pricing, Shelly bridge the gap between simple consumer plug-and-play gadgets and professional high-end building management systems.
For users in France and across Europe, ordering directly from [shelly.com/fr](https://shelly.com/fr) guarantees high quality, certified hardware that transforms traditional homes into modern, energy-efficient smart environments without sacrificing reliability or aesthetic freedom.
Frequently Asked Questions (FAQs)
Do I need a neutral wire to install Shelly relays?
Most standard Shelly relays (like Shelly Plus 1 and 1PM) require a neutral wire () inside the wall box. However, products like Shelly Dimmer 2 can operate in no-neutral configurations when installed with a bypass load on lower-wattage lighting circuits.
What happens if my home Wi-Fi goes down?
Your manual wall switches will continue to work normally to turn lights and loads on and off. Local schedules and internal mJS scripts stored on device microcontrollers will also continue to execute offline. However, remote control via smartphone outside the local network will be unavailable until Wi-Fi is restored.
Can I use Shelly relays to control motorized roller shutters (volets roulants)?
Yes. The Shelly Plus 2PM features a dedicated “Cover Mode” specifically engineered to control dual-direction motorized roller shutters, blinds, and awnings, including full position calibration (e.g., setting blinds to 40% open).
Is Shelly Cloud mandatory to use Shelly devices?
No. Cloud connection is entirely optional. You can configure and control Shelly devices purely through their internal local web server, local HTTP REST endpoints, MQTT, or direct local hub integrations like Home Assistant.
Can I install Shelly devices in standard French electrical wall boxes?
Yes. Shelly relays are among the smallest in the world. They are specifically sized to fit into standard 40mm and 50mm deep European flush-mounting boxes (boîtes d’encastrement) behind existing switches or sockets.
Final Conclusion
If you are looking to build a flexible, reliable, and energy-aware smart home without breaking the bank or replacing your existing switch plates, Shelly is one of the absolute best options on the market today. Its commitment to local control, open protocols, compact design, and top-tier energy monitoring makes it an easy top recommendation for both beginners and seasoned home automation experts alike.
