A PoE Switch does not generate power.  It obtains power from a power source such as an UPS (Uninterruptible Power Supply) or a wall socket.  The PoE Switch sends both data and power on standard Ethernet cables to other devices that are linked to it.  

There are several arrangements for supplying data and power from a PoE Switch:

     Directly to PoE PD (see diagram in Keyword End Span)
    
     Through a Splitter to a Non PoE networked device 
     (see diagram in Keyword Splitter)