Siemens 6ES5928-3UB11 Central Controller Module

Core Processing Unit for SIMATIC S5-135U/155U Systems

The 6ES5928-3UB11 central controller module, also known as the CPU 928B, serves as the core processing unit for SIMATIC S5-135U and S5-155U programmable controllers . This processor module handles all control logic execution and data management. It supports both monoprocessor and multiprocessor configurations within the S5-135U/155U rack systems .

Technical Specifications

Memory Architecture and Program Execution

The 6ES5928-3UB11 features a versatile memory architecture with 46 KB of internal RAM dedicated to user data storage . This memory can expand externally up to 64 KB using RAM or EPROM submodules for storing control programs . The CPU runs the user program cyclically and processes interrupts deterministically. LED indicators on the front panel provide status information for “Run,” “Stop,” and “BASP” (digital outputs disabled) states . The module resets completely using an “overall reset” function .

System Integration and Multiprocessing Capabilities

This CPU supports both monoprocessor and multiprocessor configurations when combined with a coordinator module . The 6ES5928-3UB11 integrates with digital and analog I/O modules via the S5 backplane bus. It also accommodates communication processors for extended network connectivity. Users configure and program the module through STEP 5 software.

Physical Characteristics

The 6ES5928-3UB11 weighs approximately 1.0 kg and fits standard S5-135U/155U rack slots . Its dimensions are consistent with standard S5 module formats . The module’s compact design allows dense configurations within the chassis. Users can mount and replace the module easily during maintenance operations.