This product appears in our “Rated Devices” list based on our experience and evaluation criteria. It is not an official approval, certification, endorsement, or guarantee of performance or safety in any specific installation. Safe operation depends on correct system design, installation, and use.
The M5Stack Atomic POE Base is an Ethernet adapter that can be used with any of the M5 Stack Atom units. It gives 100Mb/s wired Ethernet which can be powered by POE:
- Supports the Atom Lite, Atom Matrix, AtomS3 and AtomS3 Lite
- Supports PoE IEEE802.3 AF
- Wired ethernet access
- Supports 8 independent hardware sockets for simultaneous communication
- Supports TCP, UDP, ICMP, IPv4, ARP, IGMP, PPPoE protocols
- Integrated 10BaseT / 100Base-T Ethernet PHY
If wired ethernet is important or there are no power supply cables possible, but there is an ethernet cable, this is a great option.
Summary
If you are not interested in the technical detail of the device, then just read this summary and skip the rest. This controller accessory is great for van automation to add ethernet access to a Atom based M5Stack controller.
- Pros
- PoE Standard IEEE802.3 AF
- Well-supported by modern IoT stacks (ESPHome, Home Assistant, Arduino)
- Powered by the idle pin (10M/100M Ethernet), J4&J5 (VC-), J7&J8 (VC+)
- Cons
- Limited temperature rating vs. realistic van extremes
- Power consumption is acceptable but not ultra-low for battery-only devices
Can be integrated to Home Assistant
The device uses a standard W5500 Ethernet chip which is well supported by ESPHome, Arduino, ESP-IDF, and PlatformIO, so it is very compatible with Home Assistant and definitely fulfills our first requirement.
Suitable for a vehicle
For a van, it’s very suitable as:
- Small
- Low power
- Well supported
Power
The unit is powered by the idle pin (10M/100M Ethernet), J4&J5 (VC-), J7&J8 (VC+) and therefore will be 37–57 V DC. It uses a KTA1136 PoE PD + DC-DC controller. The unit will output 5V DC, maximum 1.2A for the relevant Atom controllers.
Temperature range
The official docs list operating temperature around 0–40 °C. Due to this relatively small temperature range, placement is important. In a van, interior hardware in summer sun can exceed 60 °C near the roof or windows and in winter can easily go below 0C if heating fails or the van is parked up.
So while many devices will run outside the stated range, you should assume this is not rated for the extremes of a parked van in hot summer or cold winter. Mount it in more thermally stable locations (inside cabinets, away from roof metal). Avoid placing it directly against exterior panels or inside poorly ventilated boxes.
Do not use this controller accessory for any critical systems if you expect frequent extremes (e.g. ski trips, desert heat), an industrial-temp or automotive-grade controller would be safer for critical systems.
Limitations
None known.
Use Cases
If wired ethernet is important, or there are no power supply cables possible but there is an ethernet cable, this is a great option.
Price/Quality
The item typically sells for approximately £20-£23 in the UK and we believe that is a good price for all that functionality, but remember it is a hobby dev board and as such we would not recommend it for constant extreme temperatures for critical systems. We will have some other approved devices better suited to extreme temperatures for critical systems.
This item is available in our shop