Yes and No.
Yes If you're using the single port POE Injector (APOE02-WM) you must use a power supply. The power supply connects to the POE injector and injects power across the Ethernet Cable to your POE capable unit
No If you're using either the 8 Port or 12 Port Rackmount POE injector a power supply is not required to power the unit as power is supplied by the injector for all the ports.
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