Siemens 6ES7315-2EH14-0AB0 S7-300 PLC CPU Module

Siemens SIMATIC S7-300 CPU 315-2 PN/DP (6ES7315-2EH14-0AB0) is a mid‑range central processing unit for the S7‑300 family, delivering 384 KB of integrated work memory and dual communication interfaces: MPI/DP at 12 Mbps for PROFIBUS DP and PROFINET Ethernet with a built‑in 2‑port switch for industrial Ethernet networking. It supports isochronous mode via PROFIBUS DP or PROFINET, enabling deterministic synchronization in motion control and multi‑axis applications. The module is powered from 24 V DC with a rated current of 750 mA (no‑load ~150 mA) and an inrush of about 4 A; power loss is typ. 4.65 W, and mains buffering provides stored energy for ~5 ms during voltage faults. Memory is fixed at 384 KB of work memory (no expandable RAM), with plug‑in MMC support up to 8 MB for load and backup memory; MMC backing ensures program and data retention with an expected data management window of at least 10 years after the last programming. Firmware is listed as V3.2, and the CPU supports up to 1,024 blocks in total (DBs, FCs, FBs), with the maximum loadable blocks influenced by MMC capacity. Intended for S7‑300 installations that need both MPI/DP and PROFINET connectivity, this CPU module is used in automation tasks that blend legacy PROFIBUS control with modern Ethernet fieldbus communication.