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Short answer: Seeed’s XIAO 2-Channel Wi-Fi AC Relay is an inexpensive, maker-focused board for controlling two AC circuits from Home Assistant through ESPHome, with onboard power-monitoring hardware. Seeed’s store listed SKU 114993526 at $19.90 and in stock on August 18, 2026. It is a strong fit for experienced Home Assistant and ESPHome users, but it should not be treated as a beginner-safe plug-and-play mains installation or as a universal 10-amp appliance switch.
Product page: Seeed XIAO 2-Channel Wi-Fi AC Relay.
What Seeed is selling
The product is currently listed as the XIAO 2-Channel Wi-Fi AC Relay. It combines a XIAO ESP32-C3 controller with two mains-switched relay outputs, AC input and output terminals, relay-driver circuitry, a mains power supply, fuse and sampling sections, and a BL0942 power-metering IC.
The XIAO ESP32-C3 provides 2.4 GHz Wi-Fi and is based on an ESP32-C3 platform with a single 32-bit RISC-V core, up to 160 MHz clock speed, 400 kB of static RAM and 4 MB of flash. The finished relay may not use every capability of the controller: Bluetooth 5.0 Low Energy and Bluetooth Mesh support belong to the platform and should not be assumed to be enabled or useful in the shipped firmware.
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Seeed’s published schematic shows the XIAO module, two relay sections, separate driver circuitry, AC terminals, mains sampling, fuse and power-supply sections. The schematic is useful for understanding the design, but it is not a substitute for a safety certification file, enclosure fire-rating information, relay derating tables or independent electrical testing.
#1 Best Overall
- COMPATIBLE DEVICE: 1-Channel relay module designed specifically for Seeed Studio XIAO development boards for easy integration and control.
- RELAY CONTROL: Single channel relay enables switching of high-power devices and circuits through low-power microcontroller signals.
- COMPACT DESIGN: Space-saving add-on module maintains the small form factor of XIAO boards while adding relay functionality.
- EASY INTEGRATION: Simple plug-and-play connection to XIAO boards allows quick setup without complex wiring or soldering.
- VERSATILE APPLICATIONS: Ideal for home automation projects, IoT devices, and electronic switching applications requiring relay control.
Check the current product listing carefully to confirm exactly what is included in the package. The product is built around a XIAO board and relay board, while Seeed also presents related XIAO boards and bundle options. Do not assume that a separate XIAO board, USB cable, enclosure or installation hardware is included unless the selected option says so.
Seeed’s schematic is available as a PDF.
Why ESPHome matters
ESPHome is the firmware and configuration layer that lets a microcontroller expose switches, sensors and diagnostics to Home Assistant. Home Assistant communicates with ESPHome devices through its native API rather than requiring a vendor cloud service. The integration is local-first and normally provides persistent, near-real-time updates.
That does not mean the relay works through every network outage. The board still needs power and local Wi-Fi for normal network control. If the access point, router, DHCP service, VLAN path or Home Assistant host fails, control from Home Assistant may also fail unless the firmware provides an independent fallback or local control method.
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1Fix the driver behind crashes, sound loss and screen glitches2Clear out junk files and repair common Windows errors3Scan for outdated or missing drivers - takes under a minuteESPHome also makes the device more flexible than a fixed cloud appliance. However, the exact entities and configuration depend on Seeed’s shipped firmware. Do not assume that the relay uses particular entity names, has encryption enabled, exposes both metering channels or supports effortless reflashing without first checking Seeed’s current documentation.
Connecting it to Home Assistant
The general setup path is:
- Power the relay and configure its Wi-Fi according to Seeed’s current instructions.
- In Home Assistant, open Settings > Devices & services.
- If the relay is discovered, select it and complete setup.
- If it is not discovered, select Add Integration, choose ESPHome, and enter the relay’s hostname or IP address.
- Use port 6053 unless the device documentation specifies another port.
- If API encryption is enabled, enter the device’s Noise PSK. Home Assistant describes this as a 32-byte base64-encoded key.
- Check that both relay switches and the available power sensors appear.
Home Assistant’s official ESPHome documentation confirms automatic discovery, the manual integration path and the default API port.
Discovery commonly fails when Home Assistant and the relay are on different VLANs, when mDNS or multicast is blocked, when Wi-Fi credentials were not configured, or when the device has a different hostname than expected. In those cases, find the relay’s IP address in the router and add it manually. Also check firewall rules and whether the device is fully booted.
Rank #2
- 【ESP32-C3 RISC-V Development Board】 Built with the ESP32-C3 32-bit RISC-V chip (160MHz), featuring Arduino/CircuitPython support and multiple development ports. Ideal for IoT and edge AI projects.
- 【Outstanding RF & Long-Range Connectivity】 Equipped with U.FL antenna for stable Wi-Fi/BLE5.0 communication over 100m. Complete RF performance ensures reliable IoT connectivity.
- 【Ultra-Low Power & Battery-Friendly】 4 working modes, including deep sleep at 44μA. Onboard battery charge IC supports Li-ion/LiPo, perfect for wearables and wireless IoT.
- 【Thumb-Sized & Production-Ready】 Compact 21x17.5mm design with SMD/Breadboard-friendly layout. Single-sided component mounting ensures sleek integration into wearables.
- 【Rich I/O & Edge Computing】 11 digital I/O (PWM) + 4 analog I/O (ADC), plus UART/IIC/SPI/IIS ports. Optimized for TinyML and edge AI applications.
Power is not the same as energy
Power is the instantaneous rate of electricity use, measured in watts or kilowatts. Energy is the accumulated amount used over time, measured in kilowatt-hours. A relay that exposes a power sensor in watts does not automatically provide a historical energy sensor in kilowatt-hours.
Before configuring the Energy dashboard, open Developer Tools > States and inspect every relevant entity. Confirm:
- Whether the value is instantaneous power or cumulative energy.
- The unit of measurement: W or kW for power, kWh for energy.
- The device class.
- The state class.
- Whether the reading belongs to relay channel one, channel two or an aggregate.
- Whether the value updates sensibly when the connected load changes.
Home Assistant’s Energy dashboard expects correctly classified entities. If the relay exposes only instantaneous power, Home Assistant can derive accumulated energy using the Riemann sum integral integration, provided the source sensor has suitable metadata. The result will depend on update frequency, sensor quality and periods when the device is offline.
Adding it to the Energy dashboard
- Verify that the relay exposes a valid cumulative energy entity, or create one from a valid power entity using the Riemann sum integral integration.
- Open Home Assistant’s Energy configuration.
- Add the relay under individual-device energy usage.
- Select the correct energy entity.
- Optionally select the associated power entity for live readings.
Connecting through ESPHome does not automatically make a device suitable for the Energy dashboard. If switches appear but sensors do not, inspect disabled entities, firmware configuration, units and metadata. Home Assistant’s guidance on Energy management, individual devices and Energy dashboard troubleshooting explains the required entity behavior.
Published electrical ratings—and what they do not prove
Launch coverage described two 100–250 VAC relay channels rated at up to 10 A, a combined maximum load of 2,400 W at 240 V, and BL0942 metering with a claimed measurement error of 0.1%. These figures should be treated as manufacturer or launch claims, not independent safety or accuracy test results.
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Repair common Windows errors and clear accumulated junk for a smoother, more stable PC - no reinstall needed.Free scan · no reinstallThe number “10 A” is not a universal guarantee that every appliance drawing less than 10 A is suitable. Safe operation also depends on:
Rank #3
- Flexible MCU Board: Incorporate the ESP32-C3 32-bit RISC-V chip, operating up to 160 MHz, mounted multiple development ports,
- Developer Friendly: Compatible with Arduino IDE, MicroPython, CircuitPython, PlatformIO, ESP IDF, Zephyr, Matter, ESPNow, Meshtastic, WLED, ESPHome, Home Assistant, Ubidots
- Outstanding RF performance: Complete Wi-Fi functions and Bluetooth Low Energy, while supporting communication over 100m with anFL antenna
- Elaborate Power Design: 4 working modes as low as 44 μA in deep sleep mode, while supporting lithium battery charge management
- Thumb-sized Design: 21 x 17.5mm, Seeed Studio XIAO series classic form factor
- Whether the load is resistive, inductive or electronically controlled.
- Startup and inrush current.
- Power factor.
- Ambient temperature and enclosure ventilation.
- Terminal, conductor and PCB temperature.
- How both channels are loaded simultaneously.
- Continuous-load derating and local electrical rules.
Resistive heaters and incandescent lamps are comparatively straightforward loads, but they still involve hazardous mains voltage and must remain within the complete installation’s limits. LED drivers can produce high inrush currents. Motors, pumps, compressors, transformers and HVAC equipment can stress relay contacts even when their normal running current appears acceptable. Refrigerators and high-current heaters deserve particular caution and may require a properly selected contactor or purpose-built control product.
Do not describe this relay as suitable for “any appliance up to 10 A.” Before installation, verify the exact per-channel and aggregate ratings in Seeed’s current documentation, identify the load type and check the manufacturer’s inrush requirements.
What the 0.1% metering claim means
The BL0942 is the metering component identified in the published schematic, while the launch report attributes a 0.1% power-usage measurement error to the design. That is a claimed specification, not a laboratory result independently verified across different loads.
Real-world readings may vary with power factor, low-power operation, nonlinear LED supplies, the current-sensing implementation, calibration, line voltage, temperature and firmware sampling. The result may also differ between channels or between an individual channel and an aggregate reading.
If the number matters for billing, energy audits or engineering decisions, compare the relay with a calibrated meter under the actual loads you intend to control. Treat the Home Assistant reading as an automation and monitoring input until its accuracy has been verified for your installation.
Mains safety is the central limitation
This is a mains-voltage control board, not a low-voltage Grove module or a harmless GPIO accessory. Mains wiring should be performed by a qualified person where required by local law.
Rank #4
- 5V Relay Module: Working Voltage: DC 5V; Maximum Load: AC 250V/10A, DC 30V/10A; Trigger Current of Opto-Isolator: 5mA
- Fault-Tolerant Design: Fault Tolerant Design, Even if the Control Line is Broken, the Relay will not Operate;All Interfaces of Relay can be Wired Out Through the Terminals Directly,Normally Open and Normally Closed
- Optocoupler Isolation:1 Channel Relay Board use Optocoupler Isolation that has Strong Driving Ability and Stable Performance ,The Isolation Circuit Prevent Damages to I / O Port by Relay Switch Current
- Jumper Design: The Relay Module has a Jumper That You Can Set Rather the Unit State Changes with High or Low Signal. Has Screw Terminals for Relay (NC,C,NO) and for Input; Coil +, Coil - and Trigger.
- Wide Application: DC 5V Relay Module Works Well with ARM /PIC /AVR /MCU/Raspberry/CNC Machine/ PS4 etc.
- Disconnect power and verify that the circuit is dead before wiring.
- Use conductors, terminals, fusing, strain relief and an enclosure suitable for the circuit.
- Prevent access to live terminals after installation.
- Follow local electrical codes and inspection requirements.
- Do not place the board in a wall box unless its enclosure, thermal behavior, wiring and approvals support that use.
- Do not treat a 3D-printed enclosure as proof of fire, impact or electrical safety compliance.
- Do not use Home Assistant automations as the only safety control for heaters, pumps, life-safety equipment or critical appliances.
- Remember that opening a relay circuit is not necessarily an electrically isolated or fail-safe disconnect for every purpose.
The available evidence confirms a published schematic and product claims, but it does not establish a verified UL, ETL, CE, UKCA or other certification claim for the complete installation. Certification status should be confirmed directly from current Seeed documentation and the product marking before specifying it for regulated or permanent work.
Open hardware and customization
The XIAO format makes the design familiar to makers and potentially easier to modify than a sealed consumer appliance. The public schematic documents the major circuit sections, and ESPHome provides a route to custom entities, automations and diagnostics.
That openness has limits. A schematic does not prove safe creepage and clearance, enclosure performance, thermal margins, relay contact life or regulatory compliance. Likewise, the fact that a controller can be reflashed does not establish that the current board has a simple or documented recovery procedure. Use Seeed’s current wiki and shipped firmware information before changing the device.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Alternatives
Shelly Plus 2PM
A Shelly Plus 2PM is the more natural choice for users prioritizing a polished commercial ecosystem, established documentation, app support and an installation-oriented product. The Seeed board is more attractive when low cost, XIAO hardware and maker-oriented experimentation matter more. Check the current Shelly model, availability, ratings and installation requirements before purchasing.
Official page: Shelly Plus 2PM.
Sonoff DUALR3
The Sonoff DUALR3 is a familiar two-channel consumer DIY relay with broad community awareness. It may be preferable where local availability and an established consumer product matter. Firmware behavior, local-control options, power monitoring, certification and ratings can vary by exact model and firmware, so compare the specific hardware rather than relying on the product family name.
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Official page: Sonoff DUALR3.
Smart plugs
A smart plug is usually the safer and simpler direction when the appliance has a standard plug, only one device needs control and no permanent wiring is required. It is a poor substitute when two independent circuits are needed, when direct terminal wiring is required or when the plug-in form factor does not suit the installation.
Best Value
- POWERFUL DUAL-BAND MCU BOARD – Powered by the ESP32-C5 32-bit RISC-V processor running up to 240MHz, this compact MCU board is the first XIAO to support both 2.4GHz and 5GHz Wi-Fi 6, delivering faster, more flexible connectivity for IoT, smart home, and embedded projects.
- PRE-SOLDERED FOR FASTER PROTOTYPING – Factory-installed pin headers let you connect the board directly to breadboards, expansion boards, sensors, and other hardware without soldering the headers yourself, making development and testing faster and easier.
- VERSATILE MULTI-PROTOCOL CONNECTIVITY – Go beyond Wi-Fi with Bluetooth 5 LE and IEEE 802.15.4 support for Zigbee and Thread, enabling connected devices across Matter and other IoT application ecosystems.
- EXPANDED MEMORY FOR COMPLEX PROJECTS – Equipped with 8MB PSRAM and 8MB Flash to support more capable wireless applications, data processing, multitasking, and feature-rich embedded development.
- THUMB-SIZED DESIGN WITH XIAO EXPANDABILITY – Fit powerful wireless development into the compact 21 × 17.8mm XIAO form factor. Built-in battery charge management, Arduino support, and I2C, SPI, dual UART, GPIO/PWM, and ADC interfaces make it easy to build portable devices and connect sensors, displays, modules, and custom hardware.
Zigbee and Z-Wave relays
Zigbee or Z-Wave may be better when the home already has a reliable mesh network and reducing Wi-Fi device dependence is important. They require a compatible coordinator and have different device, range and installation considerations. The Seeed relay is a better fit for users specifically seeking ESPHome customization and direct local Wi-Fi integration.
Who should buy it?
Choose the Seeed relay if you already use Home Assistant, need two AC-switched channels, want local Wi-Fi control and power monitoring, are comfortable with ESPHome, and can safely handle or outsource mains wiring. It is particularly compelling for technically capable makers who value a compact XIAO-based design at a listed price of $19.90.
Choose another product if you need a proven in-wall installation product, a plug-in appliance with no exposed mains terminals, Zigbee, Z-Wave, Matter or Thread, dependable operation when Wi-Fi is unavailable, independently verified metering accuracy, or control of demanding motors, compressors or heaters without further electrical engineering.
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Pre-installation checklist
- Confirm the current product name, package contents, firmware and Seeed setup instructions.
- Verify per-channel and aggregate ratings from current documentation.
- Identify the load type, running current, power factor and inrush current.
- Confirm that the terminals, conductors, fuse and enclosure are appropriate.
- Check local electrical requirements and whether professional installation is mandatory.
- Plan what happens if Wi-Fi, Home Assistant or the relay power supply fails.
- Inspect Home Assistant entities for correct units, device class and state class.
- Confirm whether the device exposes power, energy or both.
- Test each output with a non-critical load before connecting the final equipment.
- Provide a safe manual override or separate protective control where the application requires it.
Bottom line
The XIAO 2-Channel Wi-Fi AC Relay is an appealing low-cost building block for Home Assistant users who want two mains outputs, ESPHome integration and onboard monitoring in one maker-oriented design. Its value is the combination of those features—not simply the presence of a Wi-Fi relay.
Its limitations are equally important: the 10 A, 2,400 W and 0.1% figures are claims that require context; power readings may need conversion before they work in the Energy dashboard; Wi-Fi remains a dependency; and the published schematic does not by itself prove installation safety or certification. Treat it as a project component for competent electrical work, not as a universal replacement for a certified smart plug or in-wall relay.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
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