CPU 315-2 DP Sourcing Guide (2025 Discontinuation)

The market for the Siemens SIMATIC S7-300 CPU 315-2 DP is currently in a critical transition phase. As a legacy industrial powerhouse, it is shifting from an active product to a spare-parts-only market as Siemens pushes migration to the S7-1500 family. Siemens Industrialmonitordirect

Market Trends & Availability

* Active Phase-out: The S7-300 series reached the PM400 (Phase-out Announcement) milestone on October 1, 2023. Siemens

* Discontinuation Deadline: Effective October 1, 2025, the CPU 315-2 DP will reach PM410 (Type Discontinuation), meaning it will no longer be available as a new part from Siemens. Siemens

* Secondary Market Surge: There is high demand in the secondary and B2B markets for both new-old-stock (NOS) and refurbished units. Prices currently range from $135 to $799 depending on condition and firmware version. Alibaba Alibaba

* Support Window: Siemens typically guarantees spare parts and repair services for 10 years after type discontinuation, extending support until approximately 2033. Industrialmonitordirect Industrialmonitordirect

Strategic Insights

* Migration Urgency: For new installations, the S7-1500 is the mandatory standard. For existing plants, migration planning should begin immediately to avoid escalating costs and lead times for legacy parts. Siemens

* Technical Shift: The move from PROFIBUS DP (native to the 315-2 DP) to PROFINET is the primary architectural trend. Modern replacements focus on IIoT readiness and higher processing speeds. Industrialmonitordirect Industrialmonitordirect

* Cost Management: As 2025 approaches, "new" units in the open market are expected to command a significant premium. Procurement teams are advised to secure critical spares now. Industrialmonitordirect

I have compiled a list of current market listings for the CPU 315-2 DP and its S7-1500 successors below.