CPU 1517F-3 PN — failsafe controller with integrated safety
The Siemens 6ES7517-3FP00-0AB0 is a SIMATIC S7-1500 CPU 1517F-3 PN, a failsafe controller that runs safety programs up to PROFIsafe V2.4 / V2.6. It supports LAD and FBD with failsafe extensions, so you can program safety logic in the same environment as standard control. The CPU carries 32 kbyte each of inputs and outputs in the process image, with 16 channels available. On the network side, it includes two PROFINET ports at 100 Mbps, supports MRP as redundancy manager or client, and handles MODBUS TCP, UDP, TCP/IP, DHCP, DNS, LLDP, SNMP, and DCP. It also serves HTTP and HTTPS standard and user pages. Note that IRT is not supported, so MRPD is not available — the CPU uses RT communication for isochronous applications. The hardware clock keeps time across power cycles. Programming languages include LAD, FBD, STL, SCL, and GRAPH — the kit is complete for any IEC 61131-3 workflow.
Integration notes
Dimensions: 175 mm wide, 147 mm high, 129 mm deep. The RS-485 interface (X3) is available for Modbus RTU or point-to-point links. Up to 8 communication modules (CM/CP) can be inserted for PROFIBUS, additional PROFINET, or Ethernet. The CPU includes ERROR and MAINT LEDs for quick fault isolation. Forcing is supported for standard logic but not for failsafe programs. The I2t rating is 0.02 A²·s — relevant for sizing the power supply's inrush handling. Built-in PID controllers cover temperature and valve positioning, each with integrated optimization. This saves a separate loop controller for simple process loops.