Sonoff MINI-ZBD Review: The Zigbee Dry Contact Switch That Does Everything

If you’ve ever tried to add smart control to a garage door, boiler, electric gate, or irrigation valve — you already know the frustration. Most smart switches send voltage to the output. Most dry-contact modules are Wi-Fi only or powered by DC. Very few combine both AC and DC input, Zigbee, NO/NC support, and act as a Zigbee router.

The Sonoff MINI-ZBD does all four. At €15.33.

This review covers everything: what it is, how it works, real use cases, Home Assistant integration, and how it compares to the competition.


What Is the Sonoff MINI-ZBD?

The MINI-ZBD is Sonoff’s latest Zigbee dry contact smart switch. Unlike a standard relay (which switches 230V AC directly), this module uses a potential-free dry contact relay — its output terminals carry no voltage. They simply close or open a circuit.

That makes it safe and compatible with virtually any system that accepts a dry contact signal, regardless of the voltage or load on the controlled side.

Official price: €15.33

👉 Buy the Sonoff MINI-ZBD — Official Store


MINI-ZBD vs MINI-D: Which One Should You Get?

Sonoff already had the MINI-D — a Wi-Fi + Matter dry contact switch. The MINI-ZBD is its Zigbee sibling. Here’s how they compare:

Feature MINI-D (Matter over Wi-Fi) MINI-ZBD (Zigbee)
Protocol Wi-Fi 2.4 GHz + Matter Zigbee 3.0
Hub required No, but if it´s used by a matter ecosystem a Matter HUB is required Yes (Zigbee hub)
Zigbee mesh router ✅ Yes
Home Assistant Via Matter Native Zigbee (Z2M / ZHA)
Latency Medium Very low
Power draw Higher Lower
Price ~€13 €15.33

Bottom line: if you already have a Zigbee hub (or plan to buy one), the MINI-ZBD is the better choice. Zigbee mesh networks are more reliable, lower latency, and lower power than Wi-Fi — especially for automations that need to respond instantly, like garage doors.


Key Features

AC and DC Power Input

This is the standout spec. The MINI-ZBD accepts:

  • 110–240V AC — standard mains wiring
  • 12–48V DC — solar panels, battery banks, RV/boat 12V systems

No extra converters needed. You can install it in a standard electrical panel or directly inside a 12V DC setup. Just don’t connect both sources simultaneously.

Dry Contact Output — NO and NC Modes

The output relay supports both:

  • NO (Normally Open): circuit open at rest, closes when activated
  • NC (Normally Closed): circuit closed at rest, opens when activated

This gives you full flexibility to integrate with systems regardless of their default state — without modifying existing wiring.

DC Motor and Solenoid Valve Control

The MINI-ZBD can directly drive DC loads up to 8W on its output terminals — small motors, solenoid valves, low-power actuators. No intermediate relay needed for these applications.

⚠️ Output terminals only support DC loads. Never connect 230V AC to the output side.

High-Power Expansion via Contactors

For heavy loads (central AC units, large pumps, industrial lighting), pair the MINI-ZBD with an external contactor. The MINI-ZBD sends a low-power signal to the contactor coil, which then switches the high-power load. This is standard industrial practice — and it means you get smart control of heavy equipment for the price of a €15 module plus a contactor.

Zigbee Router (Signal Repeater)

Every MINI-ZBD also works as a Zigbee mesh router. It extends the coverage of your network, eliminates dead spots, and makes the mesh more resilient. Especially useful in larger homes or properties with thick walls.


Full Technical Specifications

Parameter Value
Model MINI-ZBD
Protocol Zigbee 3.0 / IEEE 802.15.4
Chipset EFR32MG21
Power input 100–240V~ 50/60Hz 0.1A / 12–48V⎓ 1A
Max output load 24V⎓ 2A (resistive) / 12–24V⎓ 8W (DC motor)
Dimensions 41 × 43 × 21.5 mm
Weight 34.5 g
Housing PC plastic
Operating temperature -10°C to 40°C
Humidity 5–95% RH, non-condensing
Relay cycles 20,000
Wire section 0.75–1.5 mm² (18–14 AWG)
Certifications CE / FCC / RoHS

6 Real Use Cases

1. Smart Garage Door Opener

The MINI-ZBD’s primary use case. Most garage door motors (Chamberlain, Came, BFT, Hormann, Somfy, Liftmaster…) have a dry contact input for their wall button. Connect the MINI-ZBD to those terminals and you get:

  • Remote open/close from anywhere via eWeLink or Home Assistant
  • Alert if door stays open more than X minutes (will need a door/window sensor)
  • Voice control via Alexa or Google

Set the relay to pulse/momentary mode so it simulates a button press rather than holding the circuit closed.

2. Boiler and Heating System Control

Most gas boilers, heat pumps, and underfloor heating systems use a dry contact thermostat input. Replace your dumb wall thermostat connection with the MINI-ZBD and you get full smart control: schedules, remote access, temperature-based automation, and energy-saving scenes.

Compatible with SG-Ready heat pumps for dynamic control based on electricity tariffs.

3. Smart Irrigation

Control 12V or 24V DC solenoid valves directly (up to 8W) without needing a separate irrigation controller. Build custom watering schedules, trigger irrigation from a soil moisture sensor, or pause watering when rain is detected.

4. Electric Gates and Access Control

Same dry-contact interface as garage doors. Control sliding gates, barrier arms, door strike plates, and building entry systems — fully integrated into your smart home.

5. Home Theater Motorized Screen

Electric projection screens use dry contact signals to raise and lower. Wire the MINI-ZBD and automate your setup: press one button and the screen drops, the lights dim, the projector turns on.

6. RV, Camper, and Marine 12V Systems

Thanks to DC input support, the MINI-ZBD works directly from 12V or 24V systems — no transformer. Automate pumps, fans, awnings, or other dry-contact output devicves on a boat or camper van with Zigbee, from your phone.


Home Assistant Integration

The MINI-ZBD integrates natively with Home Assistant via Zigbee2MQTT or ZHA. The EFR32MG21 chipset is well-supported by both.

Zigbee2MQTT Setup

  1. Add the device to your Zigbee coordinator while it’s in pairing mode (hold the button until the LED blinks fast)
  2. It will appear automatically in Z2M — no manual fingerprint needed
  3. Expose as a switch entity in HA
  4. For garage door use: create a cover template that tracks open/closed state using a separate tilt or contact sensor

ZHA Setup

Same pairing process. The device appears as a standard on/off switch. Use HA automations to set pulse mode behavior.

Local Control

Once paired, all control is 100% local. No cloud dependency, no internet required. Automations run instantly even if Sonoff’s servers are down.


Compatible Hubs

The MINI-ZBD requires a Zigbee coordinator or hub. Compatible options:

Sonoff ecosystem:

  • Sonoff ZBBridge-P — dedicated Zigbee hub with eWeLink
  • Sonoff NSPanel Pro — touchscreen panel with built-in Zigbee
  • Sonoff iHost — local NAS with Zigbee coordinator

Home Assistant:

  • Any Zigbee coordinator (Sonoff Zigbee USB Dongle Plus, ConBee II, HUSBZB-1, etc.)
  • Works with Zigbee2MQTT and ZHA

Apple Home:

  • Via Matter Bridge: ZBBridge-U or eWeLink CUBE

Amazon Alexa / Google Home:

  • Via eWeLink cloud-to-cloud integration

Samsung SmartThings:


Step-by-Step Installation Guide

⚠️ Always work with power OFF. If you’re not comfortable with electrical wiring, hire a qualified electrician.

What You Need

  • Sonoff MINI-ZBD
  • Compatible Zigbee hub
  • eWeLink app (for initial pairing)
  • Multimeter
  • Small flathead screwdriver

Step 1 — Plan Your Wiring

Identify the dry contact terminals on the device you want to control (garage motor, boiler, etc.). Check whether it needs NO or NC. Consult the motor’s wiring diagram if unsure.

Step 2 — Connect the Power Supply

Connect line and neutral (AC) or positive and negative (DC) to the MINI-ZBD’s power input terminals (N, L for AC / DC+, DC− for DC).

Step 3 — Connect the Dry Contact Output

Wire COM and NO (or NC) from the MINI-ZBD to the dry contact input on the device being controlled. No voltage flows through these wires — they just open or close the circuit.

Step 4 — Pair with Your Hub

  1. Power on the MINI-ZBD
  2. Hold the button until LED blinks rapidly (pairing mode)
  3. Add it through your hub’s interface (eWeLink, Z2M, ZHA)
  4. Done — the device is online

Step 5 — Configure Relay Mode

In eWeLink or Home Assistant, set the relay behavior:

  • Pulse / Momentary mode — for garage doors and gates (brief closure)

How Does It Compare to the Competition?

Device Protocol Price AC input DC input Zigbee router NO/NC
Sonoff MINI-ZBD Zigbee 3.0 €15.33 ✅ 12–48V
Sonoff MINI-D Wi-Fi + Matter ~€13 ✅ 12–48V
Shelly 1 Mini Gen4 Wi-Fi + Zigbee + Matter ~€16–18 ✅ (Zigbee mode)
MHCOZY Zigbee ZG-001 Zigbee 3.0 ~€10–12 Partial ✅ 5–32V DC
Generic Tuya Zigbee Zigbee 3.0 ~€8–12 ✅ DC only

The MINI-ZBD stands out for combining mains AC input, DC flexibility, Zigbee mesh routing, and NO/NC support — all from a trusted brand with firmware updates, CE certification, and proper customer support.

The Shelly 1 Mini Gen4 is its closest competitor. The Shelly wins on raw switching current (8A vs dry contact only) but loses on AC+DC dual power flexibility and its Zigbee mode requires separate configuration.


Is the Sonoff MINI-ZBD Worth Buying?

Yes — if these apply to you:

✅ You already have or plan to buy a Zigbee hub
✅ You want to automate a device that uses a dry contact input (garage door, boiler, gate, irrigation…)
✅ Your installation has DC power (solar, 12V, batteries)
✅ You use Home Assistant or eWeLink
✅ You want to extend your Zigbee mesh at the same time

Skip it if:

❌ You don’t have a Zigbee hub — get the MINI-D (Wi-Fi, no hub needed) instead
❌ You need to switch a 230V AC load directly — use the MINIR4 Extreme instead
❌ You already use Tuya and don’t want to move to eWeLink ecosystem


Where to Buy

Official Sonoff Store (Recommended)

Shipped from EU warehouse, 2-year warranty, 30-day no-questions returns.

👉 Buy the Sonoff MINI-ZBD — Official Store (€15.33)

💡 Register on the Sonoff store and get a $5 voucher on your first order. Free shipping on orders over $89.


Frequently Asked Questions

Does the MINI-ZBD work without a hub?
No. Zigbee requires a coordinator or hub. If you want a hub-free setup, the MINI-D (Wi-Fi + Matter) is the alternative.

Can I control a 230V AC lamp directly from the output?
No. The output is dry contact, DC only. Never connect AC loads to the output terminals. Use the MINIR4 Extreme for direct 230V switching.

Is it supported by Zigbee2MQTT?
Yes. The EFR32MG21 chipset is standard Zigbee 3.0 and the device is recognized by both Zigbee2MQTT and ZHA.

What happens to the relay state after a power cut?
The relay returns to its configured default state (NO or NC) when power is restored. You can configure post-power behavior in eWeLink.

Can I use it to open my garage door remotely while abroad?
Yes. Through the eWeLink app with an active internet connection, you can trigger the relay from anywhere in the world.

Can I connect two power sources (AC and DC) simultaneously?
No. Only one power source at a time. Connecting both simultaneously may damage the device.


Final Verdict

The Sonoff MINI-ZBD is a remarkably capable device for its price point. If you need Zigbee dry contact control — for a garage door, boiler, gate, irrigation, or any DC automation — this is one of the best options on the market right now.

It solves real problems: dual AC/DC power, genuine NO/NC dry contact, Zigbee mesh routing, and native Home Assistant support, all packed into a module smaller than a matchbox.

At €15.33 from the official store, it’s hard to justify anything else.

👉 Get the Sonoff MINI-ZBD from the Official Store


Have questions about installation or a specific use case? Drop them in the comments — I’ll help you figure out the wiring.

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