EquipVector
Evidence-backed decisions for obsolete industrial parts

Siemens · S7-300 · PLC CPU · CPU 315-2 DP S7-300 (2AH14 revision)

Siemens 6ES7 315-2AH14-0AB0

Phase-out started (PM400)

Analysis reviewed: September 11, 2026

What should replace this part?

No exact replacement has been verified. The documented migration path is S7-1500 platform. This is a platform migration, not a drop-in swap.

Select the S7-1500 target by PROFIBUS needs; confirm CPU and memory card

Your options

Move to the S7-1500 platform
A new rail with an S7-1500 CPU and SM modules on TIA Portal. Keeping PROFIBUS means a DP-capable CPU, a CM/CP module, or an IE/PB link.
Source used or refurbished stock
No used or refurbished channel is confirmed for this exact model. Check with the MLFB from your nameplate.

What will need to change?

HardwareThe S7-300 rail gives way to an S7-1500 rail. Existing SM modules do not carry over.
WiringRewire the front connectors to the new modules.
SoftwareMove the STEP 7 Classic project to TIA Portal, then fix the converted project by hand.
CommunicationsMPI and PROFIBUS DP give way to PROFINET. DP slaves need a converter or a DP-capable CPU.
AccessoriesOrder a 6ES7954-series SIMATIC memory card. The S7-1500 CPU will not run without one.

For anything not listed here, check the replacement manual against your existing configuration.

Need help confirming this replacement?

Send us the part number and current setup for 6ES7 315-2AH14-0AB0. We'll help determine whether you need a replacement, repair, original-stock sourcing, or a migration.

Request a replacement review

Can I still buy the original?

Repair — Not confirmed for this exact modelUsed — Not confirmed for this exact modelRefurbished — Not confirmed for this exact model

We did not verify current new-original stock for this exact part.

Lifecycle

Status: Phase-out started (PM400)

Discontinuation date: October 1, 2023 (family PM400; unit flag unconfirmed)

Lifecycle source · support.industry.siemens.com

Technical evidence

The recommendation above is based on the sources listed here. OEM source means the manufacturer published it; third-party source means a distributor, repair company or reseller states it. Confidence reflects how directly those sources support the recommendation: High — directly supported by manufacturer documentation. Medium — supported by family-level, secondary, or otherwise less-direct evidence. Low — limited or indirect evidence; verify independently before ordering.

OEM / manufacturer sources

OEM source Confidence: Medium Siemens Industry Support
Siemens migration guide 109478811 covers S7-300/400 to S7-1500 hardware and software conversion.
Source excerpt“Hardware migration + software conversion + recommendations for S7-300/400 to S7-1500”
View source · Note: The guide contents were confirmed through indexed content. Siemens' SIOS page gates direct access.
OEM source Confidence: Medium Siemens SIOS datasheet
The Siemens datasheet confirms this unit: CPU 315-2DP with 256 KB, firmware V3.3, STEP 7 V5.x, and MMC.
Source excerpt“CPU 315-2 DP 256KB work memory, firmware V3.3, MMC required, STEP7 V5.x”
View source · Note: Identity confirmed through indexed content. The unit-level lifecycle flag is unconfirmed.

Third-party sources

Third-party source Confidence: Low TCI Supply (distributor technical) · 2026-01-25
A distributor cross-reference points the 315-2AH14 (256 KB) at the 1513 class with a memory card, and warns that 1511 CPUs have no PROFIBUS DP.
Source excerpt“315-2AH14 -> 1513 class + 6ES7954 SMC (mandatory); PROFIBUS needs DP-capable target”
View source · Note: Distributor mapping, not a manufacturer statement. The memory-card requirement and the PROFIBUS limit are the decision-critical parts.

Limitation: The 1513-class pointer comes from a distributor cross-reference, not Siemens, and the unit-level lifecycle flag is unconfirmed. Choose a DP-capable target if your field devices need PROFIBUS.

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