If we look at data ports such as USB, we will see that these also have the ability to power the devices to which they are connected, in addition to being used to transmit data. Well, Power Over Ethernet or PoE allows the classic RJ-45 port not only to transmit data, but also to power the devices that use the classic network port and so we are talking about incorporating the power supply into a LAN. standard Infrastructure.
The standard was designed so that the different elements that make up the local network or LAN do not require complex power systems and can feed each other. It is a regulated standard under IEEE 802.3af as a base standard, but since then it has evolved over time in terms of specifications along with other well-known standards such as PoE + and Hi-Poe.
The main advantage of using PoE in a network is that considerably reduces the number of cables necessary to set up a network and reduces network costs. And how is the power supplied? Use some of the pins for communication to transmit power. However, all devices with an Ethernet port are PoE compliant.
Where is PoE technology used?
It’s already clear to us that PoE is used to power different devices through the Ethernet cable, but what can it be for? Well, in the face of the growing market based on the Internet of Things. For example, we may want to set up a smart lighting infrastructure in a building, apartment or house where each of the lights is intelligently dimmed.
Regarding devices, PoE technology is used in the point of sale terminals used by different stores, where they combine power and internet connection in one cable. Not to mention security systems such as cameras that record data and store data on a hard drive through a network interface or in the cloud.
Nor can we forget about large internal communication networks, such as those found in large hospitals and factories, where energy consumption and infrastructure are critical. Not only in terms of costs, but also in the speed of the intercommunication infrastructure between the different agents.
Why do I want a PoE capable Raspberry Pi?
First of all, it will allow you to connect your Raspberry Pi to a router with PoE support and use it to power your single board computer, which is remembered is limited to the Pi 3B + and Pi 4 models. In order to create a network of several Raspberry Pi interconnected with each other in a small industrial network. For example, you can use your Raspberry Pi to control a 3D printer remotely using a network interface.
Another advantage is for video, let’s not forget that the Ethernet standard does not use electrical signals, but optical. Which is ideal for being able to connect an IP camera and use it as a long distance CCTV system. Even if in general the idea is none other than to create a small-scale industrial infrastructure or a workshop coordinated by several Raspberry Pi.
For the classic use of the Raspberry Pi with which many associate this device, this is in principle not useful, since this SBC is wrongly associated with the use of emulators of old systems, but let’s not forget that the The utility of an SBC goes further than being a material for playful uses. Raspberry Pi is used today for various functions in a number of different industries and the PoE module is great for removing excess cables in them.
HAT PoE + Raspberry Pi
If you want to adopt a PoE module for your Raspberry Pi 3B + or Pi 4, we recommend that you buy the Pi PoE + HAT before the standard POE model, the reason is that the standard PoE model works with up to 13W consumption and this is not a problem if we consider that a large number of devices with such a power interface do not require more than this power.
The problem arises when we use the Raspberry Pi 4, which requires 9W, leaving only 4W with the rest of the hardware, including the PoE card. This is why there is HAT PoE + Raspberry Pi, who uses 802.3at standard, a more advanced version of the standard which can supply up to 25W of power without losing backward compatibility. Of course, you’ll need a PoE + compatible router, but in return you’ll be able to connect devices that require more power and even overclock your Raspberry Pi.
