This Tuya 5.8GHz presence sensor has been sitting in a box in my office for months, waiting for it’s time to be tested. I finally decided to take it out last week and install it on an office window, overlooking my desk and workbench.
In this article, I’m sharing my experience with this Tuya ZG-205Z 5.8GHz Zigbee Presence Sensor. I got it from AliExpress for less than $15. I highly suggest reading my review before buying this device.
Technical Specification
- Model: ZG-205Z
- Connectivity Protocol: Zigbee 3.0
- Radar Frequency: 5.8G/24G
- Working Current: ≤70mA
- Operating Temperature: -10°C~+55°C
- Operating Temperature: 0-95%RH
- Illuminance Range: 0-3000x.
- Power Supply: USB-C 5V1A
- Dimensions: 72x32x20mm
- Price and Availability: < $15 on AliExpress
Teardown
The Tuya Zigbee Presence Sensor ZG-205Z ships in a small box containing the device itself, a user manual and a USB-C cable for power. There is no adapter included, you will have to supply it yourself. Packaging is standard for cheap AliExpress devices, as is the shipping damage that comes with it.
This device is shaped almost exactly like the battery-powered Tuya ZG-204ZM. There is no PIR sensor mounted on the front, but the shape, size, mounting stand and indicator light are identical. The USB-C connector is set on the side, which I’m not sure I’m a fan of. It will be difficult to hide the cable once this presence sensor is installed in place.
Dismantling this Tuya presence sensor was fairly easy and simple, as all I had to do was pry it open with the flathead pry tool from my Kaiweets screwdriver set. The first thing you notice once open is the black PCB, typically found in Aqara devices. The PCB layout and design is clear and uncluttered.
The Tuya ZG-205Z presence sensor uses the Telink TLSR8258 [Datasheet] as a communication module, which can be used for both Zigbee and Bluetooth connectivity. This SoC is found in cheap Xiaomi Bluetooth thermometers, which I wrote about converting to Zigbee.
You can check out the flashing guides for the LYWSD03MMC and CGDK2.
The mmWave sensor appear to be the FR58 5.8GHz [Datasheet], a Chinese-made sensor found in cheap Tuya devices. This sensor also powers the Sonoff SNZB-06P Presence Sensor which turned out to be really solid. Even though this mmWave radar does not seem very promising to me, I’ve learnt through years of testing not to judge a book by it’s cover.
Home Assistant Integration
The Tuya ZG-205Z Presence Sensor is fully supported in Zigbee2MQTT and partially in ZHA. To pair it, you need to hold the button for about 5 seconds until the LED indicator starts blinking.
Zigbee2MQTT
Once added to Zigbee2MQTT, it’s identified as Zigbee model TS0225 by manufacturer _TZE200_2aaelwxk. It operates as a router, capable or relaying network traffic from nearby devices back to the coordinator.
The image is incorrect as the external converter is recycled from another, very similar model.
What really caught me off guard is the amount of configuration entities this device exposes in Zigbee2MQTT. I did not expect such a large number of variables from a 5.8GHz device. You can set the small, medium and large detection sensitivity and range to fine-tune the operation of the sensor.
The motion state also changes from none, small, medium and large depending on what the sensor reads and at what distance. The presence sensor is condition by the state of this entity, changing to away only when motion changes to none.
This is a fairly standard set of configuration parameters in Tuya presence sensors, and after a whole lot of tinkering I found out the best settings for my setup were:
- Large motion sensitivity: 10
- Large motion distance: 8
- Medium motion sensitivity: 10
- Medium motion distance: 4
- Small motion sensitivity: 10
- Small motion distance: 3
- Fading time: 15 seconds
ZHA
The sensor is partially supported in ZHA, as no configuration entities are available. The only thing usable is the motion entity, which operates by a default set of configuration parameters. These are reset to their default value as soon as the device is set to pairing mode and there is no easy way to change them as is.
A custom quirk found here can be applied which enables all configuration parameters, but since I don’t use ZHA as a daily driver I decided not to bother with it.
Testing and performance
After deploying the Tuya ZG-205Z in my office and tinkering with the parameters for a few days, I feel I’ve gained a solid understanding of it’s capability and performance level. For reference, it’s paired to a rock-solid mesh network operated by the SMLight SLZB-06p7 PoE coordinator.
In terms of initial detection, the Tuya ZG-205Z is very sensitive, triggering even at the slightest movement. It can reliable detect me coming into the room from a distance of about 6 meters, without any false positive triggers.
The detection angle is also quite wide. I turned the device towards one corner of the room, narrowing it’s field of view significantly and it still detected movement without issues. I tested the angle from several distances and it’s reaction time is very fast and reliable.
Unfortunately, this is where the pros of this presence sensor stop. Static presence detection range is very limited and it falls short behind many other models I’ve tested (recently this Tuya 24Ghz model).
I can only describe it’s performance as weird. Where other (bad) presence sensors perform unreliably across the board, at different distances and with different settings, the Tuya ZG-205Z performs unreliably only above 2 meters.
When I’m sitting in front of the sensor at a distance of about 1.5 meters, the Tuya ZG-205Z operates perfectly. No hiccups, no false negatives. Moving at about 2 meters, it would frequently give me false negatives. At 3 meters, and the device becomes completely unreliable.
After tweaking the parameters so many times and trying out different configuration sets, I would say that this sensor can reliably detect static presence only at a distance of about 1.5 meters. Anything beyond that, and the Tuya ZG-205Z is as good as trash.
Summary
Ultimately, the Tuya ZG-205Z is an unreliable presence sensor. Even though the mmWave radar is capable enough to perform better than it does, it’s most likely utilized badly in this presence sensor. While it operated better in the Sonoff SNZB-06P, it’s completely gimped in the Tuya ZG-205Z.
What’s weird though, is the fact that the device operates very reliably as a motion sensor. It triggers immediately whenever something moves in it’s vicinity, changing state without any delays. As soon as you stop moving, it fails to detect your static presence above 1.5 meters.
Even if you think of a use case that would not require a distance larger than 1.5 meters, I see no reason to get this model over something like the Tuya 24GHz or Tuya MTG075-ZB-RL. Much more reliable devices at about the same price tag.
Pricing and Availability
This device is priced bellow $13 on AliExpress, but I would say that even this low price tag is a waste of money. I highly suggest you take a look at these following alternatives, within a similar price range:
- Tuya 24GHz Round _TZE204_ztqnh5cg [AliExpress]
- Tuya 24GHz Ceiling MTG075-ZB-RL [AliExpress]
- Tuya 24GHz Battery ZG-204ZM [AliExpress]
If you are looking for the best presence sensor out here, without compromises, I highly suggest the Apollo MSR-2. It uses ESPHome, works completely locally and can be tweaked to infinity.
