Cisco aironet 2800 series Deployment Manual page 47

AP 2800 and AP 3800 Powering Options
Cisco AP 2800 and AP 3800 easily function with 802.3at powering systems and for advanced features like
module support (AP 3800) Cisco UPoE can be used.
Figure 44: AP 2800 and AP 3800 requires an 802.3at or better PoE source
If an 802.3at or better power source is not available, the following Cisco mid-span injectors may be used.
Figure 45: Low cost 802.3at GbE injector for AP 2800 and AP 3800 (if mGig is not required)
Cisco Aironet Series 2800/3800 Access Point Deployment Guide
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