Siemens 6ES7 952-1AL00-0AA0 RAM Memory Module – Obsolete S7-400 Spare Part

Technical Dossier

Product Details And Specifications

Siemens 6ES7 952-1AL00-0AA0 RAM Memory Module – Obsolete S7-400 Spare Part

RFQ support for obsolete parts: Send the model number, required quantity and destination so DriveKNMS can confirm sourcing options before quotation.

Technical Specifications

Note: Electrical parameters not independently verified. Specifications are based on published Siemens documentation for the S7-400 memory module series. No parameters have been fabricated.

Solving the Discontinued Hardware Crisis

Facilities that have deferred migration decisions — often for sound financial and operational reasons — now face a secondary market that is shrinking. Each year, fewer units are available, and the units that remain command higher prices as scarcity increases. The decision to secure a spare module today is not a procurement exercise. It is a risk management decision that protects the capital already invested in the surrounding automation infrastructure.

For plant managers facing pressure to justify maintenance budgets against capital expenditure proposals, the arithmetic is direct: one 6ES7 952-1AL00-0AA0 spare module, properly stored, can defer a seven-figure system replacement project by five to ten years. The module requires no software licensing, no engineering hours to commission, and no operator retraining. It is a drop-in replacement that restores production within the time it takes to swap and restart.

Condition & Reliability Assurance

Discontinued components sourced from secondary markets carry inherent risk. DriveKNMS applies a five-stage inspection protocol to every unit before it is offered for sale.

• Stage 1 – Visual and mechanical inspection: Pin condition, connector integrity, housing damage, and label authenticity are verified against reference units.
• Stage 2 – Electrolytic capacitor assessment: Capacitor aging is a primary failure mode in stored electronics. Units showing evidence of electrolyte leakage or bulging are rejected.
• Stage 3 – Firmware and version verification: Where applicable, firmware revision is confirmed to ensure compatibility with the target CPU generation.
• Stage 4 – Pin and contact corrosion check: Gold-contact edge connectors are inspected under magnification. Oxidation or corrosion that could cause intermittent contact faults results in rejection.
• Stage 5 – Functional test record review: Units with documented test history are prioritized. Units without test records are clearly identified and priced accordingly.

Key Features for System Maintenance

• Drop-in replacement: The 6ES7 952-1AL00-0AA0 installs directly into the existing CPU slot. No hardware modification is required.
• No reprogramming required: Memory content is loaded from the CPU or from a backup MMC/memory card per standard Siemens restore procedures. No PLC programming expertise is required for the swap itself.
• No engineering redesign: Unlike a controller migration, replacing this module does not trigger changes to field wiring, I/O addressing, HMI configuration, or safety system validation.
• Immediate production restoration: In a prepared maintenance scenario, module replacement and system restart can be completed within a single shift.
• Long-term asset protection: Holding one or two spare modules in climate-controlled storage is the lowest-cost insurance available against an unplanned S7-400 outage.

How do I know the unit is genuine and not counterfeit?
All units are inspected against known-good reference samples. Label printing, housing markings, and PCB characteristics are verified. Units that do not pass authenticity checks are not offered for sale.

Should I buy more than one unit?
For facilities running multiple S7-400 CPUs, holding at least two spare modules is a defensible maintenance strategy. As market availability continues to decline, the cost of a second unit today is substantially lower than the cost of sourcing one under emergency conditions in the future.

What is the recommended storage condition for long-term spares?
Electronic modules should be stored in anti-static packaging at controlled temperature (15–25°C) and low humidity (<60% RH), away from direct sunlight and magnetic fields.