The Siemens 6ES7516-2PP03-0AB0 is a CPU 1516pro-2 PN for the ET 200pro distributed I/O system, carrying 2 MB of program memory and 7.5 MB of data memory, with dual PROFINET interfaces (IRT with 3-port switch and RT) and IP65/67 protection. That IP rating means the CPU runs without an enclosure in wet or dusty environments — it is rated for direct mounting on machine frames or conveyors where a standard IP20 controller would need a cabinet.
Integration notes
The CPU requires a separate SIMATIC Memory Card (not included) to load the firmware and application, and a matching connection module for the ET 200pro base unit. The two PROFINET ports allow a line topology without an external switch; the IRT interface supports isochronous motion control cycles down to 6 ns bit performance.