Siemens 6ES5941-7UA12 Serial Communication Interface Module

Siemens 6ES5941-7UA12 is a CPU 941 Zentralbaustein (central processing unit) designed for the SIMATIC S5-115U controller family, and it is listed in catalogs and reseller listings as the CPU 941 central unit for S5 systems. This module provides 2 KB of RAM for program storage and data handling, and it functions as the primary processing element within the S5-115U central unit, orchestrating the execution of user programs and management of I/O operations in legacy Siemens automation setups. The part number 6ES5941-7UA12 is explicitly associated with the S5-115U configuration, confirming its role within that platform. Availability on multiple marketplaces—including JC-Electronics, Rexel, and eBay—reflects its status as a recognized replacement part for aging Siemens S5 installations, where the CPU 941 central unit remains a common maintenance item. This designation situates the 6ES5941-7UA12 squarely within the Siemens S5 family’s CPU lineup, and it is documented in supplier catalogs as the CPU 941 Zentralbaustein for the S5-115U.