Shelly 1PM Mini Gen4 Smart Relay Switch: Compact 8A Power

At 34 x 29 x 16 mm and 18 grams, the Shelly 1PM Mini Gen4 is small enough to disappear inside a wall box behind an existing switch. That's the point. It's an 8A relay with real power metering built in, so it can switch a light or fan and tell you, within about 1 percent, how much that circuit actually draws. Data lives both on the device and in the cloud, and it talks Wi-Fi, Bluetooth, Zigbee, and Matter. Cutting a bill or wiring up a first automation, you get the same thing: a compact switch that reports back, without the bulk of a plug-in module.

What You Get

Overview

The Shelly 1PM Mini Gen4 smart relay switch packs multiprotocol control into a footprint smaller than a matchbook. It measures power draw in real time, helping you see exactly how much energy your devices use. Its small size- just 34 x 29 x 16 mm and 18 grams-makes it ideal for retrofitting into standard electrical boxes where space is limited.

Key highlights include Wi-Fi 6, Bluetooth 5.0, Zigbee, and Matter compatibility, all powered by an upgraded ESP-Shelly-C68F processor with 8MB flash. You get local control via an embedded web interface, plus cloud access for remote operation from anywhere. An internal temperature sensor adds extra monitoring, and features like scripting, MQTT, schedules (up to 20), and webhooks (20 with 5 URLs each) enable advanced automation. This Gen4 model improves on predecessors with faster response, better memory for scripts, and multi-protocol support for future-proof installations. It's rated for 110-240V AC, handles up to 8A (2000W at 240V AC or 150W at 30V DC), and works in 30-70% RH environments up to 2000m altitude.

Load, Ports and Protocol

Built for durability and precision, the Shelly 1PM Mini Gen4 uses a dry NO contact, 1-pole micro relay with screw terminals (0.5-4 mm² conductors, 0.4 Nm torque). Power supply is 110-240V~ at 50/60Hz, with consumption under 1.2W.

Wireless specs shine: Wi-Fi (802.11 b/g/n/ax, 2412-2472 MHz, <20 dBm, up to 30m indoor/50m outdoor); Bluetooth 5.0 (2402-2480 MHz, <4 dBm, 10m/30m); Zigbee (802.15.4, 2400-2483.5 MHz, <20 dBm, 100m/300m). External protection requires a B or C curve breaker (max 10A, min 6kA interrupt). Here's a quick spec list:

• CPU: ESP-Shelly-C68F (ESP32-C6 based RISC-V)
• Memory: 8MB flash
• Max load: 8A/240V AC (2000W), 5A/30V DC (150W)
• Sensors: Internal temperature
• Operating temp: -20°C to 40°C
• Humidity: 30% to 70% RH (non-condensing)

These details ensure the device meets standards like FCC and CE for safe, reliable use.

Works With

Smooth connectivity defines the Shelly 1PM Mini Gen4. Native Matter support means it works with Apple HomeKit, Google Home, Alexa, and SmartThings out of the box-no hubs needed for basics. Zigbee extends range via meshes, while Wi-Fi and Bluetooth enable direct app control via the Shelly app.

For tinkerers, MQTT, HTTP webhooks, and scripting (JavaScript-like) allow custom logic, like auto-shutoff on high power draw. Integrate with Home Assistant or open-source platforms using the local API. Cloud syncing provides energy graphs and alerts, with ranges up to 100m indoors for Zigbee. No batteries required-it draws power from the line. Pairing takes minutes: scan QR code or use Bluetooth provisioning. This multi-protocol approach future-proofs your energy efficiency goals in mixed ecosystems.

Everyday Scenarios

The Shelly 1PM Mini Gen4 handles everyday smart home scenarios well, turning ordinary circuits into intelligent ones. Monitor and control hidden loads like under-cabinet lights or exhaust fans without visible hardware.

Practical applications include:

• Energy monitoring for holiday lights or chargers to spot vampires and save on bills.
• Automating pool pumps or heaters with schedules and power thresholds.
• Behind-wall control for garage doors or irrigation valves via voice commands.
• Temperature-based fans in server rooms or grow tents using the built-in sensor.
• Multi-device dashboards tracking whole-home energy savings via cloud data.

In rentals or retrofits, its tiny size hides easily, adding convenience without remodeling.

Setting It Up

Getting your Shelly 1PM Mini Gen4 online is straightforward, under 10 minutes for most. Always power off the circuit first.

1. Wire to live/neutral and load (consult manual for diagrams-L, N, O terminals).2. Power on; LED blinks for setup mode.
2. Download Shelly app (iOS/Android), connect via Bluetooth or Wi-Fi (2.4GHz only).
3. Scan QR or enter ID; firmware updates automatically.
4. Add to Matter/Zigbee hubs if needed, or configure MQTT/scripts via web UI (join 192.168.33.1).

Test relay toggle and power readings. Use schedules for timed operation or link to sensors. Pro tip: Enable over-power protection to avoid trips. Full docs in the app or knowledge base cover troubleshooting.

Advanced Features and Customization

Beyond basics, the Shelly 1PM Mini Gen4 supports 20 schedules and webhooks for IFTTT or custom servers. Scripting lets you code rules like "if temp >30°C and power >50W, turn off." Export energy data to spreadsheets for analysis, promoting green living.

The device's webhook capability enables integration with external automation platforms and third-party services, making it a central node in heterogeneous smart home systems. Users combine multiple 1PM Mini Gen4 units with other Shelly devices to create whole-home monitoring systems that track individual circuit loads across an entire residence. The cloud analytics engine predicts usage patterns based on historical data, enabling intelligent automations that preemptively adjust loads before peak demand periods. Pair with Shelly sensors for full-room environmental awareness via Zigbee mesh networking.

Multi-Protocol Redundancy and Future-Proofing

The Shelly 1PM Mini Gen4 implements a three-tier connectivity strategy that protects your investment against ecosystem shifts. Matter certification ensures compatibility with emerging smart home standards, while simultaneous Wi-Fi and Zigbee support means you maintain functionality regardless of which protocol dominates future deployments. This redundancy proves invaluable when network infrastructure changes-if your Zigbee mesh requires rebuilding or Wi-Fi coverage experiences temporary outage, the device continues operating through alternate pathways. Advanced users use local control through the embedded web interface, eliminating dependence on cloud services entirely. The JavaScript-like scripting engine enables sophisticated custom logic that adapts to your home's unique requirements without requiring manufacturer firmware updates.

Advanced Automation and Energy Intelligence

The combination of precise power metering, internal temperature sensing, and solid scripting capabilities unlocks advanced automation scenarios impossible with basic smart plugs. Users create sophisticated load-balancing automations that distribute demand across multiple circuits, reducing peak-hour electricity charges. The device's ability to store and report granular energy data enables identification of consumption patterns invisible to standard utility meters. Integration with Home Assistant transforms raw sensor data into predictive automations-automatically pre-cooling homes before predicted hot periods or delaying laundry loads until off-peak electricity pricing windows. The 20-webhook capacity enables deep integration with custom automation systems, allowing orchestration of dozens of devices based on complex conditional logic. These capabilities position the Shelly 1PM Mini Gen4 as a foundational component in building intelligent, responsive homes that optimize both comfort and operating costs.

Who the Shelly 1PM Mini Gen4 Is For

This one's aimed at people comfortable working behind a wall plate. If you want per-circuit power metering hidden inside existing boxes, or you run IoT gear through Home Assistant and want local control, the 8A Mini Gen4 is an easy recommendation. It rates 4.7 stars across 1250-plus reviews, mostly for its accuracy and size.

Who should pass? The 8A ceiling is the catch. That's roughly 2000W at 240V, plenty for lights, fans, and small appliances, but nowhere near enough for an oven, a water heater, or anything drawing heavy current. For those loads you want the beefier 2PM or a dedicated contactor. There's also the wiring: this goes inside a live box, so if opening a wall switch makes you nervous, hire an electrician or buy a plug-in instead. For everyone else, it does precise metering in a space nothing else fits.