SMLIGHT SLZB-MR5U Review: Two EFR32MG24 Radios with USB Over Ethernet
The SLZB-MR5U uses two Silicon Labs EFR32MG24 radios, so Zigbee and Thread each get a radio of their own and dual network mode is supported. It connects over Ethernet with PoE, USB or 2.4 GHz Wi-Fi, works as a Zigbee coordinator and router, acts as a Thread border router and supports USB over Ethernet, which lets a server use it as a remote USB radio. It suits a home that runs Zigbee and Thread together on Home Assistant or Zigbee2MQTT, and it is more than a Zigbee-only home needs.
- Running Zigbee and Thread together
- Home Assistant users
- Zigbee2MQTT users
- PoE installations
Pros
- Two EFR32MG24 radios running Zigbee and Thread at once
- Ethernet with PoE, plus USB power and 2.4 GHz Wi-Fi
- USB over Ethernet support
- Zigbee coordinator and router, and a Thread border router
- Home Assistant and Zigbee2MQTT support
- Bluetooth proxy function
- Two year warranty
Cons
- No Z-Wave radio
- No Matter bridging of existing Zigbee devices
- No Texas Instruments radio on board
- Wi-Fi is 2.4 GHz only
Who is the SLZB-MR5U for?
It suits a home adding Thread and Matter accessories to an established Zigbee network, where a single-radio coordinator would force a choice. Using the same chip family for both radios means one firmware family to learn instead of two. Ethernet with PoE lets the gateway sit in a central spot on a single cable, which is usually the best place for a coordinator, and the Thread border router role gives Thread accessories a place to attach.
What stands out on paper
Both radios are the Silicon Labs EFR32MG24, and dual network mode is supported. The radio amplifier is rated at +20dBm and the two external antennas have a gain of +5dB. Power comes from PoE or USB, and the connection can be Ethernet, USB or 2.4 GHz Wi-Fi. It supports USB over Ethernet, a feature the MR4 does not offer, and it has a Bluetooth proxy function. Both Home Assistant and Zigbee2MQTT are supported, and the warranty is two years.
What to know before you buy
There is no Z-Wave radio, and the Thread side does not bridge existing Zigbee devices into Matter. Wi-Fi is limited to the 2.4 GHz band, so the wired connection is the better choice. With two radios from the same chip family there is no Texas Instruments option on board, which matters if your setup depends on a CC-series coordinator.
Is the SLZB-MR5U worth it?
It is worth considering when you will use both protocols, want PoE and like the idea of a remote USB radio for a server that sits elsewhere. Its two-year warranty is a plus over the one-year cover of some siblings. A home that only runs Zigbee does not need the second radio, and a single-radio coordinator does the same daily job. It is a specialist network device, so expect some time on firmware and integration setup.
Frequently asked questions
Can the SLZB-MR5U run Zigbee and Thread at the same time?
Yes. Dual network mode is supported, with one EFR32MG24 radio for each protocol.
How does the SLZB-MR5U connect and get power?
It connects over Ethernet, USB or 2.4 GHz Wi-Fi, and it can be powered through PoE or USB.
Does it support USB over Ethernet?
Yes, so a server can use it as a remote USB radio over the network.
Does it work with Home Assistant and Zigbee2MQTT?
Yes, both are supported, and it also includes a Bluetooth proxy function.
Does it support Z-Wave or Matter bridging?
No. It has no Z-Wave radio and it does not bridge existing Zigbee devices into Matter, but it works as a Thread border router.
