Power over Ethernet

lastmod 2024-08-19created 2021-01-286 edits

Power over Ethernet (PoE) refers to a system that reliably transmits both data and power over an Ethernet cable. Typical PoE requires a Category 5 cable or better.

Categories

• Closed-circuit television (CCTV)
• IR Camera
• Wide dynamic range (WDR)
• onvif
• Video management system (VMS, Video management software, Video management solution)
• Network Video Recorder (NVR)
• Digital video recorder (DVR)
• Power over Ethernet (PoE)
• Twisted pair (UTP)

Types

• Power over Ethernet (PoE, PoE+, UPOE, UPOE+) | NetworkAcademy.io
• What is the difference between PoE, PoE+ and PoE++ switches? - Knowledge - Shenzhen Optico Communication Co., Ltd.

PoE

PoE (also known as the IEEE 802.3af standard) is a new standard based on the Power over Ethernet system promulgated by the IEEE 802.3 working group in 2003. The standard specifies that a powered device (PD), such as a VoIP phone, must use only two twisted pairs of the same network cable to receive power, and that PoE power consumption can reach up to 12.95W. If you want to learn more about PoE, you can click to see "Everything you want to know about PoE power supply".

A PoE switch, also called a PoE power supply switch, is an application based on PoE technology. It can simultaneously deliver power and data over a network cable to the powered terminal, and it is a switch that belongs to power sourcing equipment (PSE). If you want to learn more about PoE switches and how they work, you can click [Questions and Answers]. Why do you need a PoE switch? Typically, a PoE switch compliant with the 802.3af standard can support up to 15.4W of power per port and a supply voltage of 44V-57V. The input voltage of PoE devices connected to this PoE switch is 37V-57V.

PoE+

PoE+ (also known as the IEEE 802.3af standard) is a PoE technology standard upgraded from PoE technology, released in 2009. With the widespread adoption of PoE technology, some powered devices such as wireless APs require far more power than 12.95W. To solve this problem, the IEEE 802.3 working group released PoE+ technology, designed to deliver higher power to devices.

A PoE+ switch is similar to the PoE switch mentioned above and supplies power to PoE terminal devices over a network cable. The difference is that the maximum power per port of a PoE+ switch is 30W and the supply voltage is 50V-57V. The maximum power received by the powered device can increase to 25.5W, and the voltage can increase to 42.5V-57V.

PoE++

With the continued growth of the PoE application market, the IEEE 802.3 standard family once again introduced a new member in 2018, the IEEE 802.3bt standard. At this point PoE++ technology also emerged. Under the IEEE 802.3bt standard, PoE++ technology has two branch types. One PoE++ technology, called Type3, can be powered over two or four twisted pairs of the same network cable and can provide up to 51W of input power to the powered device. The other is Type4 PoE++ technology, which must supply power to PoE terminal devices over all pairs of the network cable, with input power reaching up to 71W. In addition, there is a PoE technology based on the IEEE 802.3bt standard called UPOE (Universal Power over Ethernet). This technology is proprietary to Cisco, its operating mode is similar to Type3 PoE technology (PoE++), and the input power it can provide to the receiving end device is 51W. Therefore, some people in the industry regard UPOE as PoE++.

When upgrading to PoE switches and PoE+ switches, a PoE++ switch can provide up to 60W of power per port for a Type3 PoE++ switch, and up to 100W for Type4. Different switches differ in output power, input power, and supported network cable types.

UPoE

How to choose

How do you buy a PoE switch compared to PoE+ and PoE++ switches?

From the introduction above, you can see that PoE switches differ from PoE+ and PoE++ switches in power supply capacity and working mode. These differences also affect their corresponding applications.

PoE switches based on the 802.3af standard generally supply 15.4W or less per port, and can connect to VoIP phones, sensors, measuring instruments, wireless APs with 2 pairs of antennas, static surveillance cameras, and other terminal devices. PoE+ switches can support high-performance movable zoom cameras, wireless APs with 6 pairs of antennas, IP phones, and so on.

Type3 PoE++ switches, with higher power supply capability, can support connections to video conferencing system accessories, building management equipment, and so on. Type4 PoE switches can support devices with high power consumption requirements, such as laptops and TVs.

Concept diagram

• PoE (Power over Ethernet) + DVR(NVR) concept diagram

Poe_camera.png Poe_camera-2.jpg

Pinouts (802.3af)

Favorite site

• Wikipedia (en) Power over Ethernet