Siemens 6ES5376-1AA11 Programmable Logic Controller

Siemens 6ES5376-1AA11 is a SIMATIC S5 memory module (Speichermodul) built around CMOS-EPROM technology, delivering 16 KB of non-volatile storage for the S5 program and data. As part of the legacy SIMATIC S5 family, the 6ES5376-1AA11 is used to store user code and configuration for older automation projects and is commonly kept as a spare part for retrofits or repairs of aging S5 installations. The module is documented in market listings as a CMOS-EPROM memory module with a 16 KB capacity, a specification that remains central to its role in small-to-mid sized S5 control applications. Typical use cases include factory automation where S5 controllers drive sequencing or simple logic, educational labs focusing on vintage Siemens hardware, and maintenance/repair scenarios requiring a genuine Siemens memory module to preserve or restore legacy programs. Variants of the part appear in the marketplace (for example references to 6ES5376-1AA11-E) but all sources consistently identify it as a 16 KB CMOS-EPROM memory module designed for SIMATIC S5 systems.