Arduino + i2c ambient sensor + Ethernet + POE

Hi All,

i'm new on this forum, so please excuse me if this is not the right place where to post this topic. I've searched the best one in my opinion.

I would like to create a very very small ambient interface sensor that could be interfaced over Ethernet, to be placed in all my rooms.

I don't want to use wifi solutions and I would like to use an ethernet connection with a passive POE running with with an industrial 24Vdc power supply, so only one Cat5e cable will be required.

I was thinking to use arduino nano + an ethernet shield with a RJ45 connector (like this Ethernet w/ MicroSD add-on for Arduino Nano) + a DC/Dc converter (from 24v to the required for Arduino) + an I2C sensor like this Adafruit BME280 I2C or SPI Temperature Humidity Pressure Sensor [STEMMA QT] : ID 2652 : $14.95 : Adafruit Industries, Unique & fun DIY electronics and kits

anyway i would need to hack the ethernet cable close to my new device in order to separate the power supply wires and route them to the dc/dc converter.

does anyone of you know if there's a component like this already on the market (at least already packaged :slight_smile: ) or do you have some other idea/suggestion to get temperature/humidity (and maybe CO2) over ethernet using a very small device?

thanks in advance for any comment