POE (Power Over Ethernet) Ethernet Power,
referring to the existing Ethernet the five basic layout framework does not
make any changes, for some based on IP terminal equipment (such as IP
telephone. Wireless LAN connect into the AP, webcams, etc.) to transmit data
signals at the same time, also can at the same time as the device itself
provides a dc Power supply technology. POE equipment including PSE output Power
equipment and Power to accept PD, heavy point discussed the Power output device
Using POE technology, users need to provide each terminal device connected to the POE wall power, thereby saving the IP phone for connection. Wireless LAN access point. Video surveillance cameras. Building management systems and remote video kiosks and other equipment required to power wiring costs.
In addition, with the aid of PoE, the enterprise will also be able to lock some key equipment on a power supply, use UPS backup power to support the whole system, so that will greatly improve the power supply security of the whole system, so as to improve the reliability and security of the whole system equipment.
2. System follow the standard
As Ethernet is used in the world is getting more populist, corresponding network equipment to develop rapidly, in the course of long-term use, to match the power supply has been the bottleneck of troubling the popularization of the network terminal equipment to further. Then, through the Ethernet cable to or standby line to achieve the standard Ethernet device power supply naturally with the development of the demand of the market and technology adoption of execution.
IEEE802.3 af standard of Ethernet power supply (POE) and the related detailed rules for the implementation of the regulations regarding. The standard as a power transmission protocol based on Ethernet, specify the corresponding transmission equipment (PSE) for the electrical equipment (PD) on the mechanism of the power supply. Including the on-line test for the electrical equipment, grading, start the power supply, a breakout protection technologies such as the detailed rules for the implementation of. Agreement also for Ethernet transmission line (PTL) has made the detailed rules.
In this paper, the system fully established on the basis of the above standard design, in the case of ensuring the security of the existing structured cabling system, ensure the normal operation of the existing network at the same time, thus minimizing the cost.
3. PoE parameters
A complete PoE system includes the supply Equipment (PSE, Power Sourcing Equipment) and the electrical Equipment (PD, Powered Device) two parts. PSE was client for Ethernet Ethernet Equipment Power supply Equipment, is also the manager of the whole process of PoE Ethernet Power supply. The PD is to accept the Power supply Equipment of PSE load, namely PoE system client devices, such as IP phone. Webcam. AP and handheld computers (pdas) or mobile phone charger and many other Ethernet devices (in fact, any Equipment Power is not more than 13 w can obtain corresponding Power from RJ45 socket). Both based on the IEEE 802.3 af standard based on electrical Equipment of PD connectivity. The Device type. Power consumption level and other aspects of information, PSE based on PD Power supply via the Ethernet.
POE standards for the main power supply characteristic parameters of the power supply system,
1. The voltage between 44 ~ 57 v, typical values for 48 v.
2. Allow the maximum current of 550 ma, the biggest starting current of 500 ma.
3. The typical working current is 10 ~ 350 ma, the overload test current is 350 ~ 350 ma.
4. Under the condition of light, the biggest need for current 5 ma.
5. Provide PD equipment in five levels of 3.84 ~ 12.95 W power request, the maximum of no more than 13 W.