Siemens 6ES7291-8GE20-0XA0 Memory Module

Flexible Data Storage for S7-200 Systems

The Siemens 6ES7291-8GE20-0XA0 memory module provides additional data storage capacity for S7-200 programmable controllers. This module expands the CPU’s memory resources, allowing more complex programs and larger data tables. Compact automation systems benefit from this upgrade without requiring a full controller replacement.

Memory Capacity and Technical Specifications

This memory module offers 64 kilobytes of EEPROM storage for user programs and configuration data. The module supports both read and write operations, enabling online program modifications without external programmers. An integrated write-protect switch prevents accidental data overwrites during normal operation. Furthermore, the EEPROM technology retains stored data for over 20 years without a battery.

Parameter	Specification
Model	Siemens 6ES7291-8GE20-0XA0
Memory Type	EEPROM
Total Capacity	64 KB
Program Storage	32 KB
Data Storage	32 KB
Data Retention	> 20 years (no battery)
Write Cycles	> 1,000,000
Access Time	< 150 ns
Interface	Proprietary S7-200 bus
Dimensions (W x H x D)	25 mm x 50 mm x 10 mm
Weight	0.02 kg
Compatible CPUs	S7-200 series (all models)

Physical Design and Connector Interface

This memory module features a compact 25 mm by 50 mm form factor with a 16-pin edge connector. The gold-plated contacts ensure reliable electrical connections through frequent insertion cycles. A write-protect slide switch on the top edge provides convenient data protection. The module’s lightweight construction of 20 grams minimizes mechanical stress on the CPU socket.

Programming and Data Management

You can access this memory module directly through the S7-200 programming software interface. The module appears as an additional data block within the CPU’s memory map. Users can copy program blocks from the CPU to the module for backup purposes. Additionally, you can transfer complete projects to multiple modules for machine standardization.

Operational Benefits and Applications

The Siemens 6ES7291-8GE20-0XA0 enables rapid machine changeover by storing multiple production recipes. This module stores timer presets, counter values, and setpoint tables for different product variants. Maintenance personnel can replace a faulty CPU and restore the program within minutes. Consequently, this memory solution reduces downtime significantly in high-mix production environments.

Installation and Compatibility Notes

You can install this memory module in any S7-200 CPU that has a dedicated memory cartridge slot. The module plugs directly into the front panel without requiring additional mounting hardware. Always power off the CPU before inserting or removing the memory module. The module supports hot swapping only on specific CPU models with live-insertion capability. Verify your CPU version supports this module’s full 64 KB capacity before purchase.