PoE (Power Over Ethernet) technology makes the installation of IP devices become simple and safe. Single Ethernet cable can carry both power and data to front-end IP devices, that means the power cord next to the IP device is eliminated. The PoE employs 48V DC low voltage power , providing a safe power system. The installers only need to wire Ethernet cable while setup the PoE IP devices.
Usually there are PSE (power supply equipment) including PoE Switch, PoE injector, PoE NVR that combine both power and data together and send through Ethernet cable. The front-end IP device such as PoE IP camera, PoE access point should have built-in PD module to separate the power from the data. It sounds a little bit complicated, fortunately, we don’t need to deal with these parts. Those components are integrated to the PSE or your PoE IP devices. What you need to do is simply plug and play, for example, the PoE IP camera will get both power and data from the PoE Switch after you link both them with Ethernet patch cord, because the power system is transparent to the network.
Single Ethernet cable supplies single PoE IP device seems fair enough. Nowadays, more and more IoT devices has been come out, you may require to add new IP devices to the scene. However, the Ethernet cable were being buried in the walls. Re-wiring a new cable costs not only the money, but also the disturbance to the business. Although wireless/WiFi is the possible path to take into consider, it could become unstable while there are walls between your IP devices and the receiver. Is there any solution to add new PoE IP devices without re-wiring the cable? You will need PoE Powered switch.
PoE Powered switch (also named power passthrough switch) can be powered by PoE injector or PoE Switch to obtain both power and network. There is no need to wire extra Ethernet cable. The existing cable can be used to expand the PoE Network in the front-end.
PoE powered Switch has been developed several years ago while PoE+ appeared. But it is not used in practice widely because the PoE+ only supplies a maximum of 25.5W power upon 100 meters distance, and the remain power is not much enough for the second switch. Thanks to IEEE802.3bt standard, The PoE injector can add 95W maximum power to the Ethernet cable. Therefore, the remain power can be up to 71W for the PoE powered switch, allowing the user to supply multiple PoE IP devices.
Let’s take 5541-25 8-port PoE powered Switch for example, What you need to do is add one 95W PoE injector and the 5541-25 PoE powered switch at both ends of your existing Ethernet cable. The PoE Network is expanded to 7 RJ45 ports and the total power budget for the front-end IP devices is 71W. As the switch is gigabit link, the network speed is enough for most of the IP applications.
Why IEEE802.3bt PoE powered switch can output such high power?
The PoE/PoE+ takes only 2 twisted pairs to send the power while actually the standard cat5e/cat6 has 4 twisted pairs cable in total. The new PoE standard occupies all 4 twisted pairs to transmit the power and data. That is why the remains power is in triple times.
Additionally, the pure copper is crucial for PoE powered switch, which is the same as any other POE solutions. That is because pure copper cable is capable to reduce the problem of power lost inline and guarantee the system to have 71W remain power beyond 100 meters transmission.
What’s more, the 95W PoE injector has already employed DC54V power instead of DC48V to reduce the power lost inline.
The PoE powered switch not only expands the RJ45 PoE ports, but also extends the PoE Network to 200 meters. PoE powered switch is also a standard Ethernet switch which provides data storage and forwarding. The new IP devices integrated to the PoE Powered switch can be placed at a distance of up to100 meters far away, which enhances the flexibility on the system update and expanding greatly. If you ask for longer PoE extending, the PoE Extender can be daisy chained up and provide 500 meters PoE Network on the end of the PoE powered switch system.
