Siemens 6ES5377-0AA32 Memory Submodule

Reliable Program Storage for S5-115U Systems

The Siemens 6ES5377-0AA32 memory submodule provides non-volatile storage for user programs in S5-115U controllers. This module plugs directly into the CPU’s dedicated memory slot for quick installation. Maintenance engineers appreciate its reliable data retention and simple replacement procedure.

Memory Capacity and Storage Technology

This submodule offers 8 kilobytes of CMOS RAM with battery backup for reliable data preservation. The memory organizes into 4 kilobytes for program code and 4 kilobytes for data blocks. A replaceable lithium battery maintains the stored content for up to 300 days without external power. Furthermore, the module supports read and write operations at cycle times under 1 microsecond.

Battery Backup and Data Integrity

The integrated lithium battery automatically activates when the main supply drops. This battery preserves all program and data blocks during maintenance or unexpected outages. A low-battery warning LED alerts users approximately 30 days before depletion. You can replace the battery without losing stored data by following the hot-swap procedure. Additionally, the module performs a cyclic redundancy check (CRC) on power-up to verify memory integrity.

Physical Design and Installation

This memory submodule features a compact, lightweight design of only 70 grams, which minimizes mechanical stress on the connector. The plastic housing with keyed pins prevents incorrect insertion into the CPU slot. A protective cover shields the battery compartment from dust and accidental contact. The module’s small footprint allows installation even in densely populated racks. Moreover, the gold-plated contacts ensure reliable electrical connections over many insertion cycles.

Operational Benefits and System Performance

The Siemens 6ES5377-0AA32 significantly reduces program load times compared to earlier EPROM-based alternatives. Users can modify program logic directly in RAM without erasing or reprogramming memory chips. This flexibility accelerates commissioning and troubleshooting processes considerably. The module also stores system diagnostics data, which aids in fault analysis after unexpected events. Consequently, this memory solution enhances overall system maintainability and uptime.

Compatibility and Ordering Information

This memory submodule fits all S5-115U CPU models with a standard memory interface. You must verify that your CPU firmware version supports 8 KB addressing before installation. The package includes the memory module, a pre-installed lithium battery, and an instruction leaflet. For extended retention periods, consider ordering spare batteries separately. Always handle the module with electrostatic discharge (ESD) precautions during installation.