802.3at

  Power over Ethernet (PoE) and Power over Ethernet Plus (PoE+) are both standards for delivering power and data over Ethernet cables, but they differ in terms of power output and application capabilities. Here’s a detailed comparison:   1. Power Delivery PoE (IEEE 802.3af): --- Maximum Power Output (at PSE - Power Sourcing Equipment): 15.4W per port --- Power Available for Devices (at PD - Powered Device): 12.95W (after accounting for power loss over the cable) --- Typical Applications: Basic IP cameras, VoIP phones, and low-power wireless access points. PoE+ (IEEE 802.3at): --- Maximum Power Output (at PSE): 30W per port --- Power Available for Devices (at PD): 25.5W --- Typical Applications: Higher-power devices such as PTZ (Pan-Tilt-Zoom) cameras, advanced wireless access points, and video phones.     2. Voltage Range PoE: --- Voltage Range: 44-57V DC PoE+: --- Voltage Range: 50-57V DC     3. Power Allocation and Usage PoE: --- Power Allocation: Provides enough power for devices with lower power requirements. PoE+: --- Power Allocation: Provides extra power for devices with higher power needs, allowing for the use of more advanced or power-hungry equipment.     4. Compatibility PoE: --- Backward Compatibility: PoE+ (802.3at) and PoE++ (802.3bt) can power devices compliant with the PoE standard (802.3af). PoE+: --- Backward Compatibility: PoE+ can power devices that comply with the PoE standard (802.3af).     5. Cable and Infrastructure PoE: --- Cable Requirements: Typically uses Cat5e or higher cables. PoE+: --- Cable Requirements: Also uses Cat5e or higher cables, but with the increased power, higher quality cables (Cat6 or Cat6a) are recommended for maintaining performance and reducing power loss.     6. Application Scenarios PoE: --- Use Cases: Ideal for basic network devices that do not require significant power, such as entry-level IP cameras, basic VoIP phones, and simple wireless access points. PoE+: --- Use Cases: Suitable for devices with higher power demands, such as advanced PTZ cameras, high-performance wireless access points, and devices with built-in heaters or lights.     Summary Table Feature PoE (IEEE 802.3af) PoE+ (IEEE 802.3at) Maximum Power Output 15.4W per port 30W per port Power Available for Devices 12.95W 25.5W Voltage Range 44-57V DC 50-57V DC Typical Devices Basic IP cameras, VoIP phones PTZ cameras, advanced WAPs, video phones Compatibility Compatible with PoE+ Backward compatible with PoE Cable Type Cat5e or higher Cat5e or higher (Cat6 recommended)     Choosing Between PoE and PoE+ PoE is suitable for most standard network devices with lower power needs. It is cost-effective and meets the requirements of basic IP devices. PoE+ should be used when devices require more power, such as high-performance cameras and advanced network equipment. It ensures that devices receive sufficient power for full functionality and additional features.     In summary, PoE+ offers more power and flexibility compared to PoE, supporting a wider range of higher-power devices and applications.