Sensors are vital to driving smart home automation. Among them, motion sensors equipped with passive infrared (PIR) are notably prevalent. You may feel strange about PIR, but you must be familiar with these sensors for their iconic dome-shaped case, a fresnel lens.

However, a significant downfall of these sensors is that they fail to detect presence when you are stationary, often leading to accidental triggers of automated systems. For instance, you may find your lights turned off while you’re still in the bath.

Presence sensors then came to change the game with advanced millimetre-wave (mmWave) solutions akin to those found in driverless vehicles. These sensors do not just detect human presence and motions, but higher-end models can also interpret your gestures and pinpoint your exact location within the room. This innovative category of sensors is hopefully to replace traditional motion sensors.

And here came one from Sonoff with an attractive price tag. I have installed one in my home for a fortnight, and here are my brief takes on the new sensor:

TL; DR

Fors:

• Attractive price
• Modern design that fits your inferior settings
• Faster than a motion sensor
• High compatibility with third-party platforms

Againsts:

• Need power supply via USB cable
• Slower than certain pricer rival in clearing speed

The orange wrapping box indicates it's a Zigbee gadget from Sonoff. It looks like a smaller security camera with a rounded body, greatly distinguished from rivals that adopt a flat design like Aqara and Tuya’s offerings.

The unit is secured on a magnetic stand, a feature that allows for convenient positional adjustments. Initially, this seems like a smart design choice, but the accompanying power cable could complicate placement. The weight of the cable could potentially drag the sensor in various directions, missing the intended detection coverage. However, Sonoff provides a cable management kit to address this issue.

If you’ve already finished renovating, it could be inconvenient to install this sensor in a bathroom because it requires a power supply via a USB brick. Most designs place the connector on the top part, which conflicts with water-resistant cases for outlets. Some vendors, such as Google Nest, use a flat charging brick that fits better. Therefore, you might need to search online to find a suitable charging brick.

If you have extra space on a shelf near your sensor, a portable power bank serves as an ideal alternative solution. This will significantly reduce the hassle of hiding and securing the cable.

The design accents fit perfectly into your home settings, whether you place them on a shelf or install them on your ceilings.

It is less elegant than the PIR sensors; the picture below provides a clear demonstration of the difference.

The pairing process for the gadget is seamless and intuitive. By simply holding down the gadget’s single button for a while, it prepares to pair with a Zigbee gateway. eWeLink app would also provide an illustrative visual guide for the setup by scanning the QR code on the sensor.

I primarily used the sensor with Sonoff iHost, a local smart home hub powered by eWeLink. I set the sensor to automate an Aqara Zigbee wall switch on the iHost.

It is easy to create a smart scene in the device, toggling your lights during the night when it sensors your presence.

One downside to the system is that it doesn’t, by default, offer options for triggering during the day or night, instead opting for fixed hours. To realize this feature, you can work around via Node-Red, but it requires additional time for learning and configuration.

The response speed is a mixed blessing. It detects people fast but requires roughly a minute to clear the status. Despite this, it’s still significantly faster than my Ikea motion sensor, which takes minutes to clear the motion detection status.

Sonoff has released a beta firmware for my device that has reduced the wait time to a mere 15 seconds. This is a substantial improvement from the previous version, and the overall user experience has been noticeably enhanced. However, when the update is officially released, you may need a Sonoff ZB Bridge-P to receive it.

Not to criticize, but it’s worth mentioning that the expensive high-end Aqara FP2 presence sensor can clear its detection status in just one second as people leave its coverage.

The Sonoff sensor provides three sensitivity steps, ranging from low to high. From my experience, selecting the “High” option in version 1.03 could cause misdetections. However, these issues have been resolved in version 1.04. Be aware if you have pets such as cats or dogs, the sensor might be triggered unintentionally.

You can find a complete detection log in your eWeLink app or iHost web UI. Additionally, you can set up notifications to alert you of any detections, either for security reasons or general monitoring.

The device also performs seamlessly with Home Assistant via ZHA integration, thanks to the devoting open-source developers. Since the device is always powered up, it serves as a Zigbee router, improving transmission with other sensors in my bathroom.

You can also add a graph to the Home Assistant dashboard to visualize detection data. This feature adds valuable insights to your home living environment.

In summary, Sonoff presents an attractive option for smart home enthusiasts. It operates efficiently with Sonoff’s local and eWeLink-connected gateways, as well as with third-party platforms like Home Assistant.

The upcoming firmware enhances the user experience, outperforming traditional PIR sensors at a comparatively low cost. However, it does lose some elegance due to its need for wired power, similar to its competition. This requirement limits installation options and compromises interior aesthetics.

Despite its lower price, the device lacks some sophisticated features that mmWave sensors offer, such as position, gesture, and sleep detection – features available in Aqara’s products.

Currently, the Sonoff SNZB-06P sensor is discounted to $14.9 on its website, offering a more reasonable option between the $9.49 SNZB-03 motion sensor and the $82.99 Aqara FP2.