Power over Ethernet technology allows power sourcing equipment (PSE)—such as a PoE switch—to simultaneously deliver both power and data over a single Ethernet cable to a powered device (PD)—like an IP camera or VoIP phone. PoE is an elegant solution for business networks of all sizes because it is easy to install and cuts costs.
The Institute of Electrical and Electronics Engineers has ratified three PoE standards describing four PoE types.
PoE Standards
Currently, there are three PoE standards that define the amount of power that PSE can supply and the maximum amount of power that a PD will receive.
IEEE 802.3af (Standard PoE)
IEEE 802.3af (also called “Standard PoE”) supplies a voltage of 44 to 57V and a current of 10-35mA. The maximum power output per port is 15.4 watts (W). Because some power is always lost during the transmission process, Standard PoE guarantees 12.95W of power to the PD. This PoE standard is what most systems use for applications such as:
- IP cameras
- VoIP phones
- Wireless Access Points (WAPs
- Powered Audio
- Switches
IEEE 802.3at (PoE+)
The IEEE 802.3at standard (also called PoE+) provides a voltage range from 50 to 57V and a supply current of 10-600mA. PoE+ increases the wattage to 30W on each port, with 25.5W for devices. PoE+ has backward compatibility with standard PoE, which means it can support devices normally used by PoE (Type 1). This standard supports PDs such as:
- IP telephones
- Alarm systems
- PTZ cameras
- Motion-tracking cameras
- Remote computer terminals
- Biometric sensors
IEEE 802.3bt (PoE++ and HI-PoE)
The latest PoE standard, IEEE 802.3bt, defines two types of wattage standards (Type 3 and Type 4). To visualize this, please refer to the table above.
Type 3 (PoE++)
The Type 3 PoE standard (referred to as PoE++) carries up to 60W for each PoE port, supplying a maximum of 51W to the PD. PDs that PoE++ commonly powers include:
- Video telephones
- Thin clients
- Door access systems
Type 4 (Hi-PoE)
Type 4 is called higher-power PoE or Hi-PoE for short and delivers up to 100W on each port, with 71W to the PD. This standard has the current maximum power rating. Both Type 3 and Type 4 standards are backward compatible with 802.3af (PoE) and 802.3at (PoE+). PDs that can be powered by Hi-PoE include:
- LCD/computer monitors
- Point-of-sale systems
- Large video signing displays
- LED lighting systems
Is PoE Technology a Good Solution for My Business Network?
Power over Ethernet is a proven solution for business networks of any size, and there are many reasons to adopt this technology.
The Benefits of PoE
PoE technology is:
- Less expensive: PoE uses a single Ethernet cable to transmit power and data in a network—fully half the cabling required with traditional electrical wiring—and without the need for an expensive electrician to install it.
- Quick and easy to install: PoE switches are simple plug-and-play devices that do not require professional expertise to install.
- Flexible: PoE technology allows PDs to be placed in any location, even in remote areas with no electrical outlets. In addition, PoE extenders can be used to increase distances beyond 100 meters, shielded cables can be used for outdoor equipment, and industrial-grade PoE devices can be deployed in harsh environments.
- Scalable: PoE devices are plug-and-play, making it simple to move or add equipment to the network.
- Safe: PoE uses relatively low voltages with a low risk of electrical danger.
- Reliable: PoE is a technology that has been proven to be dependable and sound.
Last Thoughts
Now that you have a basic understanding of PoE, its different standards, benefits, and the variety of devices that can be used, setting up a PoE network for your business should be possible. When doing so, make sure to use the correct equipment for the job, and do not forget to plan for future needs. A robust PoE network can serve your business for many years.
