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Things you should know before using Power over Ethernet (PoE)

Technology has surely change the way we live our life, information are being easily transmit, the powered devices that can only play a signal role in our daily lives, such as the computer, smart television or mobile devices can now do more things than before. Why? Because of the power of networks. And this brings us to our main topic today, the Power over Ethernet(POE) technology. In recent years, Power over Ethernet is an ever-growing phenomenon, and as we can see for ourselves its advancement is going on a stable rate.

Information is key , so it would be wise to learn some advantages of using the POE, then you will know why choose to use it and what can you benefit from it.

POE has the ability for speedy delivery of data and there is no need for AC/DC power suppliers and outlets at the ends, signal cable that can transmit both data and power. This makes it even easier to make installment, because this allows for installation of remote or outside equipment without having to connect to the AC power source. Now some of you may be worried about the safety of this technology, well, PoE-enabled devices are safe enough as it work under low voltage and it only supply correct output power to powered devices that complied with PoE standard. POE installment is also cost effective due to the fact that it can help you save substantial money by eliminating additional power lines, and compare to the fiber optic cable the Ethernet cable is cheaper and it can be manufacture in various factories.

After knowing the advantages of PoE, I guess you might be attracted and intend to set up network system by employing PoE in a suitable way, then you are supposed to pay attention to some tips if you determine to use POE technology in your network system. That being said, let’s just get straight to the point.

A complete PoE system simply consist of PSE and PD. It seems difficult to figure out these quite technology terms. Actually, PDs are the common devices that you need to find solution to supply them power to work and even network, such as IP camera, wireless access point, VoIP phone etc. And the equipment that supplies power to the network device is called a PSE(Power Source Equipment), this shouldn’t be hard to forget, because most of the PSE are either network switches or POE injectors intended for use with non-POE switches, these are the devices that you looking for your powered devices or network devices.

For making your powered devices work normally, figuring out what is the power consumption of your devices is the first step, only know exactly how much input power that you devices needed then you will get them work reliable and safely. This depends what PoE standard of PSEs you need to purchase. For the time being, there are three standards are commonly used and most of PoE-enabled devices are complied with them. Namely, IEEE 802.3af/at/bt. Each of them can supply different output power, generally IEEE 802.3af is capable to provide up to 15.44 watts of power, but in practice, powered devices (PDs) reliably receive 12.95 watts due to power losses through the circuit. While 802.3at PoE standard supports 30 watts of power, but as with the 802.3af standard, power losses lower the amount supplied to 25.5 watts. The last 802.3bt or PoE++ standard It is a higher powered PoE standard, also called the next generation standard that may provide up to 90 watts by using 4 pairs of balanced twisted-pair cabling. You are suppose to choose according to your powered devices, or they fails to work compatibly.

Additionally, your requirement on network speed is also need to be considered, 10/100Mbps and Gigabit network are available, pick the suitable one that is in line with your network devices. Gigabit network would be recommended as it is able to remain fast network speed even with signal long in the transmission. Especially for IP camera system, signal lag would cause inconvenience or even loss.

Besides that, as you know, connection between devices rely on cable. What type of cable does the POE technology required? The answer should be twist pair Ethernet cable, there are various types for you to choose, such Cat5/6/7 and even higher category. Using which option, it’s up to you. It is crucial to choose the right cable because we don’t want the outcome to be bad. The Cat5/6 cables are POE suitable, but if your budget allows, it’s far better to choose the Cat6 for these three main reasons. First is it has a larger-gauge diameter which reduce resistance and keep the power waste to minimum. Second is it has a less power loss, and the last, the cables are tightly packed up in their trays and pathways, the chance for the heat increase because it doesn’t have the chance to dissipate away from the cable. Besides, one thing need to be noted, you should use pure copper wire for the reason that in the transmission, some power wastes and turns to energy, which results in power drop. Pure copper wire is effective way to reduce sharply power drop issue, this can help your network devices receive sufficient power. Some PSE like Fiber PoE switch equips with fiber port to provide chance to have long distance fiber optic link, which finished via fiber optic cable.

As for the POE distance, power has never been the factor of its limitation, it’s the Ethernet cabling standards that limits the total length of cabling to 100 meters, that is also the furthest a POE switch can range in distance. But on the other hand , if you are looking to add more range for remote network devices, there are several practical solutions to reach long rang PoE, including POE extender(500m max.), 800M PoE switch, PoE coaxial converter(1km) as well as fiber optic devices.

How to upgrade to POE system

As usual you should connect other devices to a POE switch and the switch will automatically detect the compatible devices and enable power, make sure that the devises that you are connecting is compatible to the POE standards. Now the POE suits all applications from low cost unmanaged edge switches with a few ports up to complex multi-ports rack mounted units with sophisticated management. If you already have Ethernet switch, and want to keep it, PoE injector is useful device to make you upgrade to PoE network system even if you using the non-PoE switch.

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