Review on UCTRONICS Raspberry Pi Zero Ethernet & Power: Micro USB Ethernet/PoE Adapter for Fire TV Stick, Chromecast, Google Mini & More by Fernando Hudson

TL;DR: Power is unstable, device reboots every 2-3 minutes with no network load. I built my home automation system using microcontrollers and SBCs. , and I was looking for a way to power everything via PoE and avoid wireless communication. Using the $5 RPi0 + $20 USB PoE adapter is cheaper than the wESP32 solution and gives you much more network stack space and much more power/versatility. Making PoE relay/sensor hubs like this seems almost ideal to me. This device saves a lot of space inside the case when you don't need to make room for the PoE splitter/power adapter and USB Ethernet adapter. That's a great idea and I'm surprised there aren't any other providers doing something like this. I really wanted it to work and probably bought a few of these. The problem I have with this PoE adapter is quite strange. Use this PoE adapter connected to an 8-port PoE+ 10/100 unmanaged switch. There are no other peripherals, USB hubs (OTG), nothing connected to the GPIO pins, or extra load on the power rails - just Pi0. The Pi0 boots with no power warnings and I can access it via SSH. Looking at the syslog/persistent log/dmesg I can see that the kernel (5.10) finds and starts the eth0 interface for the RTL8152 with no problems. There are no errors, warnings, or indications of a problem in the logs. The device looks normal via USB, with no abnormalities. No packet loss or network errors. Temperature is ok (33C with sink). Core voltage is normal. So far, so good. But after 2-3 minutes of idle the Pi0 loses power and goes into a reboot loop. Here's the weird part: It only happens after the network has been idle/low load for more than 2 minutes. It keeps restarting with an open ssh connection, but NOT when I start top or see what generates non-ACK traffic through eth0. If I keep pinging the device from another computer, it never restarts/loses power. I have tested this for up to 15+ hours of constant ping and every time the ping/traffic stops the Pi loses power for 2-3 minutes. I have persistent logging enabled and there is no indication at all in the logs as to what the problem could be. This is clearly a dirty shutdown with no warnings. Monitoring the USB 5V bus voltage shows that the power goes on and off in about 0.75 seconds. I can run high CPU usage (stress) on the Pi, but it keeps restarting unless there is ALSO significant network load (i.e. constant ping from another device). I suspected a low power condition. I've tried disabling automatic device power management via sysfs config and disabling EEE (Energy Efficient Ethernet) with ethtool but not much. I even tested another (working, unmanaged) PoE switch. The same thing. The PoE device just keeps failing suddenly without putting enough strain on the network. Now when I plug in the same Pi0 with a standard 1.0a power supply and use a non-PoE network switch, it stays reliable and never generates RTL8152 related errors. The device seems to work well as an Ethernet adapter, but the PoE function was completely unreliable for me. I'm not sure if I have a faulty unit or if it's a design flaw. I have contacted UCTRONICS and will request a replacement. I will update my review when this is fixed.