The Siemens 6ES7954-8LT02-0AA0 is a spare-part SIMATIC S7 memory card designed for S7-1x00 CPUs. It provides 32 Gbyte of Flash-EPROM storage, which is the program and data load memory for the controller — not a removable USB-style drive. The 3V Flash technology means the card retains its content without a backup battery, and the 50 000 minimum write/delete cycles cover the typical program-update cadence over the life of a production line.
This part is at a mature lifecycle stage and is designated as a spare part for replacement and service support. Procurement requires a quoted-to-order RFQ against the specific order code.
Data retention and endurance
The card guarantees a minimum data retention of 10 years after the final programming action, provided the cumulative write/delete count stays under 5 000 cycles. If the write/delete count exceeds 45 000 cycles, retention drops to 1 year. For a typical PLC program that is updated a few times per year, the 50 000-cycle endurance rating is effectively a lifetime supply — the retention limit, not the cycle count, is the practical constraint for long-term archival of the production image.