Hi!
I've recently come across this small, battery-powered radar-based presence detector. This is the first time I'm testing a device using this technology, so I want to share with you how it works and how it compares to my other traditional Zigbee PIR sensors, specifically the Aqara RTCGQ11LM Motion Sensor. I also have a few other PIR sensors (Zonoff and some white-label devices), but the Aqaras are the ones I mainly use at home because they're small and aesthetically pleasing.
Overview
At first glance, the device feels solid and well-built. Its spherical design gives it a subtle “eye” look, and while it’s slightly larger than my Aqara, it’s not bulky at all. The magnetic base makes mounting quick and easy—unlike the Aqara, which sometimes has to be unmounted from the wall since its base only pivots in one direction (rotation aside). When my son first saw it, he was a little spooked by the “eye” shape (he’s wary of just about everything!), but after a few hours, and especially after I turned off the red detection LED, he completely forgot it was there, thanks to its compact size and discreet placement.
I won’t dive into the hardware specifics, as I haven’t taken it apart and prefer to keep this from a pure end-user perspective. The only hardware detail I’ll mention here is that it runs on a standard CR2450 battery. For the rest of the technical specs, several other reviews online cover it thoroughly if you’re curious.
Pairing with Zigbee2MQTT
As of Zigbee2MQTT v2.10.1, this device isn’t natively supported. However, you can easily add it by installing the external converter (link) before initiating pairing. Once the converter is in place, you’ll get full, out-of-the-box support.
Pairing itself was straightforward. After enabling pairing mode on both Z2M and the device, it was detected within seconds, exposing a full set of sensors and entities. The main ones are:
• Occupancy – A binary sensor reporting presence status.
• Presence state – A text sensor providing detailed occupancy states: absence (no one detected), presence (person detected), and sensor_close (detection zone physically obstructed or sensor disabled).
• Illuminance – Ambient light level in lux.
Several additional sensors and configuration entities are exposed, which I’ll cover in the configuration section.
One notable omission is the battery level entity. Despite running on a CR2450, the device doesn’t report its battery status. This means you’ll need to rely on usage patterns or manual testing to know when to replace it. It’s a minor drawback, but I can live with it: after all, about 90% of my other battery-powered Zigbee devices suffer from inconsistent battery reporting.
Additionally, OTA firmware updates aren’t available (at least not through the current external converter). I don't know if there is actually any OTA support using the tuya gateway as I don't have one.
Configuration
This is where you’ll want to spend some time to ensure proper calibration. It’s a bit more involved than a standard PIR sensor, but you’ll get the hang of it after a few tries.
First, there’s the Detection Range setting, which defines the maximum distance at which the device detects presence. I leave mine at the maximum (500 cm).
Two settings help fine-tune sensitivity:
• LED Indicator – Toggles the red LED off when switching from absent to present, which is handy for testing without ambient light interference.
• Energy Streaming – Reports real-time radar activity as motion energy and presence energy across 20 sub-sensors. This is incredibly useful during calibration.
Sensitivity can be set to High, Medium, Low, or Custom. Keep in mind: the higher the sensitivity, the greater the risk of false positives. In Custom mode, you can adjust the sensitivity for each of the 10 radar zones individually.
There’s also an Auto-Calibration function (triggered via a dedicated switch) that lets the device establish baseline levels, after which you can make minor manual adjustments. Pro tip: Always enable Energy Streaming before running auto-calibration, or the process will stay stuck in a “Starting” status indefinitely.
You can start with any of the three preset sensitivities to get a feel for the device, but I highly recommend using Custom mode paired with Auto-Calibration for the best results. Once calibration is complete, remember to disable Energy Streaming.
One observation: when Energy Streaming is active, the device appears to respond faster (likely because it skips deep sleep) and sensitivity seems slightly higher. Run a final test with Energy Streaming turned off to confirm normal operation.
Finally, you can configure the Presence Cooldown—the number of seconds the device waits before switching to absent if no movement is detected. While the minimum is 2 seconds, it wasn’t effective on my unit. I settled on 5 seconds, which is the lowest reliable threshold for my setup.
Testing
This is where the fun begins 
First, let’s talk about Zigbee connectivity. My ecosystem actually consists of 68 devices from various manufacturers, making it quite heterogeneous. This is the most responsive battery-operated end device I’ve tested: whenever I adjust a setting in Z2M, it acknowledges the change within ~5 seconds at most. No disconnections or re-pairing needed. It’s a major improvement over my Aqara sensors, which don’t fully comply with the Zigbee standard and occasionally need to be rejoined—especially when routed through my bTicino/Legrand routers. My only hope is that the CR2450 battery truly lasts at least a year.
To test its performance, I placed the ZPS-Z1 right next to the Aqara in my living room (securing it with temporary tape for now, as you can see in the photo above, so I can reserve the pre-applied adhesive for permanent installation ).
After a few days of testing, here’s what I found:
• The Aqara has a wider detection angle (confirmed by specs: 170° vs. 110°), thanks to its flat, fan-shaped coverage pattern compared to the Zemismart’s 360° omnidirectional field. This suggests I should have positioned the Zemismart in a more optimal location, but as mentioned, I wanted a strict 1:1 comparison. Nevertheless, the detection performance was nearly identical, with only a slightly narrower horizontal coverage compared to the Aqara. Yet it still reliably covers the areas that matter most to me.
• Where the device truly excels is in static presence detection. A clear win for the Zemismart.
Below is a side-by-side comparison of how both devices handled detection over a 2-hour period. Note that the Aqara's detection periods may appear longer due to its cooldown setting of at least a minute and a half.
Final Considerations
After a few days of real-world use, this radar-based presence detector stands out as an excellent alternative to traditional PIR sensors, especially for occupancy-based automations. It trades a slightly narrower horizontal detection angle for true static presence tracking and effortless magnetic mounting. The Zigbee responsiveness is exceptional, and Z2M integration works flawlessly once the external converter is added. The lack of battery reporting and OTA updates are minor trade-offs that are easy to work around.
I don’t plan to replace all of my current sensors with these (at least not in areas where my existing ones work reliably without frequent re-joining), but they’ll be ideal for spots where static presence detection is essential,like my living room and kitchen. I’ll only be keeping my fingers crossed that the CR2450 lasts at least a year.
Pros:
• Highly responsive Zigbee end-device (acknowledges Z2M changes in ~5s)
• True 360° omnidirectional detection + excellent static presence tracking
• Magnetic base allows flexible, tool-free repositioning
• Custom calibration with 10-zone tuning and reliable auto-calibration
• Seamless Z2M support (via external converter), rich entity exposure
• Discreet design; red LED easily disabled
Cons:
• No battery level reporting (relies on CR2450 lifespan)
• No OTA updates (at least via current external converter)
• Slightly narrower horizontal FOV (110°) compared to wide-angle PIRs
• Initial setup requires manual converter installation
• Requires more initial configuration compared to PIR sensors, which are essentially "pair and forget" devices (or, for some of my Aqara, "pair and re-pair" :|)
One final note on the technology: As mentioned, this is the first radar-based device I’ve owned, but it easily feels like the most feature-complete option in its price range.
Here is the link to the product page for anyone interested:
Feel free to write a comment if you have any questions!