PoE: Five Tips for Successful Deployment of PoE Power Supply

The article comes from PoE switch and solution provider Feng Runda. I hope everyone will take a moment to read this article carefully to understand the key points for successful deployment of PoE power supply and will help you to use PoE power supply technology correctly.

PoE power supply refers to the transmission of power while transmitting data to a network device without changing the original network architecture. The carrier is the network cable. The correct deployment of PoE is very safe and reliable, and it can also save costs. This is a relatively new network technology. If you can keep the following five tips in mind, you can ensure the successful deployment of PoE.

1, to provide sufficient power to the powered device

This one sounds easy, but in practice, it's not that simple. The IEEE802.3af standard defines a five-level power supply standard that provides 12.95W of power to a powered device. It also needs to consider the power loss caused by the cable length. Therefore, the power supply device must provide at least 15.4W per port. power. For a 24-port PoE switch, it is necessary to provide more than 370W of power, in addition, the switch also needs to consider the power required for data exchange itself.

Therefore, it is necessary to pay close attention to the power of the power supply equipment: The PoE power supply module used in the intermediate access method (also with 24 ports as an example) must not be less than 370W, and the output power of the 24-port PoE switch must be greater than 370W. The line, as to how much, depends on the power consumed by the data exchange of the switch. Normally, a non-PoE switch can be used to measure the power consumed by the switch itself. Together with the 15.4 W per port, the minimum output power required by a PoE switch can be obtained.

2. Use uninterrupted power supply equipment such as UPS

Some powered devices powered by PoE are often devices that perform mission-critical tasks, such as Internet telephony. Once the power is turned off, the voice is completely cut off and calls cannot be made. Whether it is traditional program-controlled telephone exchanges or IP telephony, it is important to maintain patency. Therefore, when designing a network, it is necessary to distinguish such critical equipment that cannot stop supplying power or stop data transmission. Use an uninterrupted power supply such as a UPS for backup power supply to keep power and data unobstructed.

3. Use switches that comply with PoE power standards

When deploying PoE, make sure that the power supply and power receivers are compatible with each other. Of course, if both the power supply equipment and the power-receiving equipment are in compliance with the PoE standard, then you are not worried. Once a certain end equipment does not claim to comply with PoE, you need to be careful.

Before using the equipment, it is recommended that you carefully read the instructions and their technical specifications. It is not possible. You must contact the manufacturer's technical support to make sure that the power supply equipment and the power receiving equipment you use are compatible with each other. If you ignore this article, you will likely have to pay the dual cost of time and money.

4, can not ignore the performance of the cable

Which type of cable are you using? It may be Cat5, or 5e, or even 6. The higher the cable level, the lower the power loss and the better the performance. There are bad manufacturers will shoddy, so need to carefully read the manufacturer's technical parameters, whether it really meets the performance of 5e or 6. If you have ample budget, try to use higher-level cables.

Another point to keep in mind is that only four nodes can exist between the switch or hub to the network card. If the intermediate access method is adopted and the PoE power supply module is used to supply power, then the module itself also needs to be a node. Many people often ask: With PoE, what is the longest cable distance? The correct answer is 100 meters from the switch/hub to the network card, not 100 meters from the PoE power supply module to the powered device, because the decision length is not the power supply but the data transfer.

5, using a more cost-effective PoE deployment method

As mentioned earlier, there are two methods for deploying PoE. One is the end access method and the other is the middle access method. The terminal access method usually uses a PoE switch as a power supply device. For new networks, this method is recommended because the topology is simple and the connection is not error-prone. Anyway, if you want to buy a new switch, you can spend more money and buy PoE switches. It is very easy.

If you recently purchased or upgraded a switch and you want to deploy a PoE device and find that the switch you just purchased is not PoE, isn't it a bit frustrating—you'll have to refinance yourself with a new, standard switch. Don't worry, one of the great benefits of PoE is that this technology does not need to uproot the original network. It can also use the convenience of this technology without having to change the existing network structure and facilities. In this case, it is recommended to use the intermediate access method to connect the existing switch and the powered device to the PoE power supply module. This is also compatible with 802.3af. The problem can be solved simply by slightly increasing the cost. .