Siemens 6ES7952-1KL00-0AA0 Flash Memory Card

6ES7952-1KL00-0AA0 — Every Minute of Downtime Costs You Money. We Ship Today.

Your S7-400 CPU is down. The line is stopped. Maintenance is standing by. The program is gone because the memory card failed — and procurement is scrambling to find a genuine replacement that can arrive before the next shift. This is exactly the scenario the 6ES7952-1KL00-0AA0 was built to resolve, and it is exactly why we stock it in Xiamen, ready to move via DHL Express within hours of order confirmation.

The 6ES7952-1KL00-0AA0 is a 2MB Flash EPROM memory card for the SIMATIC S7-400 platform. It stores the user program, data blocks, and system data in non-volatile flash — no battery, no capacitor, no data loss on power cut. When a CPU is swapped or a rack is replaced, this card is the fastest path back to a running machine. Slot it in, power up, and the CPU loads the program automatically. No STEP 7 laptop required on the floor if the card was pre-loaded.

We have supplied this part to maintenance teams in automotive plants, chemical facilities, power stations, and steel mills across Southeast Asia, the Middle East, and Europe. The procurement cycle for a genuine Siemens memory card through standard channels can run 4–8 weeks. We compress that to 3–7 business days, door to door, anywhere with a DHL or FedEx address.

URGENT REQUIREMENT? Contact: [email protected] | WhatsApp: +86 18359268345

Quick Technical Datasheet

Troubleshooting & Replacement Tips

Symptom: CPU powers on but shows STOP mode with SF LED lit, no program execution.
First check: is the memory card seated fully? The 6ES7952-1KL00-0AA0 uses a friction-fit slot — partial insertion causes read errors that the CPU logs as internal fault OB87 or OB122 triggers. Remove, inspect the gold contacts for oxidation or debris, reseat firmly until you feel the click.

Symptom: CPU displays “MEMORY RESET” request on startup after card swap.
This is expected behavior when inserting a card that was previously formatted on a different CPU or contains a project compiled for a different CPU type. Perform a complete memory reset (MRES) via the mode selector switch: turn to MRES, hold 3 seconds until STOP LED blinks, release, then turn to MRES again within 3 seconds. The CPU will clear internal RAM and load from the card on next RUN command.

Symptom: STEP 7 cannot read or write the card — “MMC access error” in diagnostics.
The 6ES7952-1KL00-0AA0 must be formatted using STEP 7’s “Memory Card” tool before first use if it arrives blank or was previously used in a different S7-400 project. Navigate to PLC → Memory Card → Format in STEP 7 v5.x. Do not attempt to format using a PC card reader — the proprietary format is not FAT-compatible.

Firmware matching: The 6ES7952-1KL00-0AA0 does not carry firmware itself — it stores the user program. However, if you are replacing a CPU alongside the card, verify that the replacement CPU’s firmware version is compatible with the STEP 7 project version. Mismatched firmware can cause OB1 load failures even with a valid card.

Address assignment: The S7-400 memory card does not use DIP switches or manual addressing. The CPU reads the card automatically on power-up. No jumper configuration is required. If you are migrating a program from a 4MB or 8MB card to this 2MB card, verify that the total compiled program size (DB + FC + FB + OB blocks) does not exceed 2MB — check via STEP 7 → PLC → Module Information → Memory.

Common fault codes to document before replacement: OB85 (program execution error), OB86 (rack failure), OB87 (communication error), OB122 (I/O access error). These help distinguish whether the memory card is the root cause or a symptom of a broader rack or backplane issue.

Reliability in Harsh Conditions

Flash EPROM is not a consumer-grade storage medium. The 6ES7952-1KL00-0AA0 is built to IEC/EN 61131-2 industrial standards, which means it has been validated against the conditions that destroy ordinary storage: continuous vibration up to 10 Hz–58 Hz at 0.075 mm amplitude and 58 Hz–150 Hz at 1g, shock loads up to 15g over 11 ms, and operating humidity from 10% to 95% non-condensing. The card has no moving parts, no electrolytic capacitors, and no battery — the three most common failure points in industrial electronics exposed to thermal cycling.

In steel mill environments where ambient temperatures near furnaces can spike well above rated limits, the card’s flash cells retain data even through thermal excursions, because the data is written at the cell level and does not depend on active power to maintain state. In offshore and coastal installations where salt-laden air accelerates corrosion on connector pins, the gold-plated contacts on the 6ES7952-1KL00-0AA0 provide significantly better corrosion resistance than tin-plated alternatives.

Every unit we ship has been visually inspected for contact integrity, label authenticity, and physical condition. We cross-reference date codes and batch markings against Siemens documentation. Counterfeit memory cards are a documented problem in the S7-400 spare parts market — they pass visual inspection but fail within weeks under load. We do not source from grey-market aggregators.

Global Express Logistics

Our warehouse is located in Xiamen, Fujian Province — one of China’s primary export hubs with direct DHL, FedEx, and UPS gateway access. For urgent orders confirmed before 14:00 CST, same-day dispatch is standard. Transit times to major industrial regions:

Every shipment includes a commercial invoice, packing list, and certificate of conformity. For orders requiring export licensing documentation or specific HS code declarations, our logistics team handles the paperwork. Anti-static packaging with moisture barrier is standard — the card arrives in the same condition it left our warehouse, regardless of how many customs checkpoints it passes through.

Tracking numbers are issued within 2 hours of dispatch. We do not use consolidation services or economy freight for industrial spare parts — when your line is down, economy shipping is not an option.

Contact Information

Email: [email protected]
WhatsApp: +86 18359268345
Web: siemensplc.com
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