Siemens 6ES7518-4FP00-0AB0 SIMATIC S7-1500F CPU 1518F-4 PN/DP 9MB/60MB Programmable Logic Controller

The Siemens 6ES7518-4FP00-0AB0 is a SIMATIC S7-1500F CPU 1518F-4 PN/DP, a fail-safe central processing unit with 9 MB of program memory and 60 MB of data memory. It offers four interfaces: PROFINET IRT with a 2-port switch, PROFINET RT, PROFINET basic services, and PROFIBUS, giving it both PROFINET and PROFIBUS connectivity in one CPU. A SIMATIC Memory Card is required to operate it.

Technical Specifications

Selection Notes

The F suffix marks this CPU as fail-safe, rated for use in SIL/PL safety programs alongside standard control logic, so it replaces a separate safety PLC in mixed standard/safety applications. The integrated PROFIBUS DP master on the fourth interface is the differentiator versus a PN-only F-CPU in the same family: it lets the controller keep existing PROFIBUS field devices in service while running PROFINET IRT for new IO, useful in retrofit projects. Against the higher-memory 1518-4 PN/DP variants without the F suffix, this one trades some throughput headroom for certified fail-safe program execution; plants with no safety-rated IO on this controller do not need the F variant.

Applications

Mixed standard and safety control on machines or lines still running legacy PROFIBUS devices alongside newer PROFINET IO, where safety shutdown logic runs on the same CPU as the process control program.