Power over Ethernet (PoE) is a standard (802.3af) for powering devices using voltage carried on “spare” wires in the Ethernet cable. For devices that support being powered by PoE, it means you only need one cable to the device to connect it to network and provide power. Only one cable to snake through walls and attics, and the device can be placed without regard to access to a power outlet.
PoE is rightfully marketed to business IT and is particularly well suited to devices such as IP security cameras, wireless access points, and IP phones. Unfortunately, targeting the business IT audience meant the devices tended to be a lot more expensive than consumer equivalents.
That is now changing. I’m finding a fair number of PoE PSE switches (PSE = Power Source Equipment, that supply power on the Ethernet wire) and PoE PD devices (PD = Powered Device) in the consumer price range. They’re still listed under “business networking” rather than “home networking”, but at least they exist.
He mainly used Netgear PoE switches; I like the MikroTik ones better.
I have been asked to document my home sensor network. Being married to a person with a background in web security sets boundary conditions:
No cloud. We are running all services locally.
No control, only metrics.
I am collecting data from a number of plugs with power meters over Wifi, using the MQTT protocol. I am also collecting data from a number of temperature sensors over Zigbee, and convert to MQTT. The MQTT data is ingested into Influx, and then read and plotted in Grafana. All of this is dockered and runs locally on an Ubuntu server.
Startup SMLIGHT has launched the SLZB-06 Zigbee 3.0 to Ethernet, USB, and WiFi adapter with PoE support that works out of the box with open-source software such as Home Assistant and Zigbee2MQTT.
The device combines Texas Instruments’ СС2652Р microcontroller for Zigbee with ESP32 for WiFi, data transfer to Ethernet or USB, and peripheral functions such as LEDs and a button.The design is complemented with Microchip LAN8720 for Ethernet.
7490 specs indicate it uses at least 1 WATT more power than the 7390
About cooling: according to the video both run the same temperature, either because the air cooling of the 7490 is better. I’m wondering if that is the same when running inside a closet.
Ein normales Kabel mit TAE-Stecker und sechspoligem RJ-Stecker, wie es für den Anschluss analoger Telefone an eine TAE-Dose verwendet wird, funktioniert nicht.
Bei entbündelten Anschlüssen (ohne analoges oder ISDN-Telefon) kann ein direktes Kabel verwendet werden.
Anonymous
The Wiert Corner - irregular stream of stuff 