Reliable 2.5G/10G Ethernet Switch
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PoE (Power over Ethernet) is defined as using an existing Ethernet cat-5 cabling infrastructure without any changes. It can provide DC power supply technology for such devices as IP phones, Wireless LAN AP, network cameras, etc… as well as transmit data signal for a Poe. Poe is also called a Pol (power over LAN) or active Ethernet (Active Ethernet), sometimes referred to as a Power over Ethernet. It is the latest standard specification for the simultaneous transmission of data and electrical power using existing standard Ethernet transmission cables and maintains compatibility with existing Ethernet systems and users.

1. PoE only needs to install a cable, which is space-saving and straightforward, and the equipment can be moved at will.
2. Cost savings. Many PD, such as video surveillance cameras, need to be installed where AC power is difficult to deploy. POE saves power and time to establish power.
3. Power Supply Intelligence, DC power as data transmission, PoE can use a simple network management protocol (SNMP) to monitor and control the device.
4. POE power supply end device will only power the device that needs power. The Ethernet cable will only have voltage present if the device that needs emphasis is connected, thus eliminating the risk of power leakage. (Security)
5. A single UPS can provide power to all devices involved in a power failure. (Centralized power supply)
6. Users can seamlessly mix legacy and POE devices on the network, which can coexist with existing Ethernet cables.
7. Makes network devices easy to manage. Because when the remote devices connect to the network, they can only control them, rewire, or reset remotely.
8. In the wireless LAN, POE can simplify RF testing; access points can be easily moved and accessed.
9. Red

1. PoE output voltage range 44-57V, PD powered voltage range 36-57V, 802.3af/at standard; refer to the following.
2. PoE power supply distance requirements are far, and the output voltage must be high.
3. For enough power, the network cable must meet the standard; The output voltage of the PoE switch within the standard (44-57V) is as high as possible.
4. The voltage of our POE product is 52V, the equivalent impedance of the CAT5E 200 m wire is 25 ohms, the AF standard current is 300 Ma, U = 0.3 * 25 = 7.5 V, 52V (Poe output)-7.5 V (attenuation voltage) = 44.5 V (200 m wire load voltage) , according to p = ui, it is concluded that the load terminal power P = load terminal voltage U * AF standard current I = 44V * 0.3A = 13.2W, which is enough for ordinary camera or wireless AP to work.

All power of the PoE switch is a significant indicator directly related to how many cameras can be brought. For a 24-port PoE switch with a 400W power supply, the total power of the PoE switch is about 370W after removing losses.

Under IEEE802.3af standard can supply full 24 ports (370/15.4=24). It can provide power to 24 cameras simultaneously, that is, full load power. But if it is calculated according to the IEEE802.3at standard of maximum power supply of 30W for a single port, it can only supply power to 12 ports at most simultaneously (370/30=12).

In our use, the maximum power consumption of many ordinary network cameras is low, basically not more than 15W. If each PoE port has the total power (such as 30W) to reserve power supply power, the port’s PoE power can not be used up, while some ports can not share the passion of the situation. Some PoE switches support dynamic power allocation, which can avoid it. When purchasing a PoE switch, see if the button supports dynamic power allocation. Each port is only allocated the actual power used so that the power of the PoE switch can be used more efficiently.