With the rapid development of network monitoring in recent years, the technical threshold is also more and more high, manufacturers provide technical support is more and more tend to be comprehensive, systematic. In the technical exchange, the most puzzled engineers have the problem of the Poe power supply, so as to enumerate some Poe knowledge and focus on the doubts.
Question 1: What is PoE technology?
PoE (Power Over Ethernet) refers to the existing Ethernet Cat.5 cabling infrastructure without any changes in the case of some IP-based terminals (such as IP phones, wireless LAN access points AP, network cameras Etc.) to transmit data, but also for such equipment to provide DC power supply technology. PoE technology can ensure the existing structured cabling safety while ensuring the normal operation of existing networks to minimize costs. A complete PoE system includes Power Sourcing Equipment (PSE) and Powered Device (PD). PSE: POE-capable Ethernet switches, routers, hubs, or other network switching devices Powered Device (PD): In the surveillance system is mainly the network camera (IPC).
Question 2: PoE power supply stable?
From a technical point of view, PoE technology for many years, is now in a very mature stage. However, due to the cost pressure on the market being monitored, the quality of the PoE switch or wire used is too poor, or the design of the solution itself is unreasonable. As a result, the work load on PoE-powered projects is particularly large. Therefore, Stable point of view.
Cable experts OPTFOCUS reminded: network monitoring project, different from the ordinary network cabling, the amount of data transmission is very large, high power, and requires 24/7 uninterrupted work, and PoE power supply technology of wire demanding, it is recommended monitoring The project, the use of OPTFOCUS quality assurance PoE equipment and wire is the stability of the entire system. Do not save the cost of online materials, outweigh the benefits.
Question three: PoE power supply program advantages?
1. Simplify wiring and save labor costs OPTFOCUS monitoring dedicated data cable "Passive 300 meters Pass" broke the original "from" limit, dedicated to long-distance HD data transmission. The second generation of products also support POE long-distance power supply applications, a data cable at the same time long-distance transmission of data and power supply, so that contractors no longer need expensive power and time spent installing power supply, design, construction greatly simplified, the overall system cost greatly reduce. (Note: Devices such as network cameras or switches need to support IEEEE 802.3 af & 802.3at, Type 2 Class 4: 25.5W (2 pairs); some infrared cameras may support only 250 meters due to power problems. The actual product test data shall prevail. )
2. Safe and Convenient The PoE powered device only provides power to the devices that need power. Only connected to the device that needs power supply, there is voltage on the Ethernet cable, thus eliminating the risk of leakage on the line. Users can safely mix existing devices and PoE devices on the network that co-exist with existing Ethernet cables.
3. Easy Remote Management Like data transfer, PoE can supervise and control this device by using Simple Network Management Protocol (SNMP). This feature can provide functions such as night shutdown, remote restart.
Question 4: What are the risks or disadvantages of PoE power supply technology in engineering application?
1. Insufficient power, fixed by the power terminal: 802.3af standard (PoE) output power is less than 15.4W, sufficient for the general IPC, but for the dome and other high-power front-end equipment, the output power up to To the request.
2. Risk is too concentrated: Generally speaking, one PoE switch will power multiple front-end IPC at the same time. Any failure of the POE power supply module of the switch will result in all the cameras fail to work and the risk is too concentrated.
3. Equipment, high maintenance costs: Compared with other power supply methods, PoE power supply technology will increase the after-sales maintenance workload, from a safe and stable sense, the stability of the power supply alone, the best security.