Product Overview

The Siemens 6ES7952-1AL00-0AA0 is a RAM memory card specifically designed for the SIMATIC S7-400 programmable logic controller (PLC) system, providing essential expansion of the CPU’s load memory capacity for storing user programs and system data . As part of the S7-400 memory card family, the Siemens 6ES7952-1AL00-0AA0 features a 2 MB capacity and utilizes the long design form factor, making it physically compatible with all S7-400 CPU models that accept RAM memory expansion cards .

The Siemens 6ES7952-1AL00-0AA0 enables users to store larger and more complex automation programs beyond the internal memory limits of the CPU. For example, earlier S7-400H CPU models with 2.8 MB program memory could benefit significantly from this 2 MB RAM card . As a volatile memory type, the Siemens 6ES7952-1AL00-0AA0 requires the CPU’s backup battery to retain data during power outages . This characteristic distinguishes it from Flash memory cards, making the Siemens 6ES7952-1AL00-0AA0 particularly suitable for applications requiring flexible, online program modifications and hardware changes without system interruption . The Siemens 6ES7952-1AL00-0AA0 is a legacy component that remains crucial for maintaining existing S7-400 installations worldwide.

 

Technical Specifications

Parameter Name	Parameter Value
Product Model	6ES7952-1AL00-0AA0
Manufacturer	Siemens
Product Type	RAM Memory Card
System Platform	SIMATIC S7-400
Memory Type	RAM (volatile)
Memory Capacity	2 MB
Physical Design	Long form factor
Voltage	5 V
Weight, approx.	40 g – 58 g
Country of Origin	Germany
EAN/UPC	4019169009935
Product Status	Legacy (spare part)

 

 

Main Features and Advantages

Optimized for Program Expansion: The Siemens 6ES7952-1AL00-0AA0 provides a cost-effective solution for expanding the load memory of S7-400 CPUs, allowing the storage of extensive user programs, including code blocks, data blocks, and system configurations . For applications with complex control logic or large data sets, the Siemens 6ES7952-1AL00-0AA0 ensures that the system can accommodate the required program footprint without necessitating a CPU upgrade.

Support for Online Program Changes: A key advantage of the Siemens 6ES7952-1AL00-0AA0 is its suitability for applications requiring runtime modifications. Systems using RAM cards support online downloading of program changes without interrupting the automation process, making the Siemens 6ES7952-1AL00-0AA0 the preferred choice for critical processes where downtime is costly and system availability is paramount . This feature is particularly valuable in PCS 7 projects where continuous operation is essential.

Simple Download and Operation: Unlike Flash memory cards, the Siemens 6ES7952-1AL00-0AA0 allows the user program to be downloaded directly from the engineering software using the standard “Download” command, simplifying the programming process . The Siemens 6ES7952-1AL00-0AA0 provides straightforward integration, reducing commissioning time and minimizing the risk of operator error during system updates.

Reliable Integration with S7-400 System: The Siemens 6ES7952-1AL00-0AA0 is fully compatible with the S7-400 platform and is designed to the same rigorous Siemens quality standards, ensuring reliable operation and robust performance in demanding industrial environments . The card’s long design and standard form factor ensure secure insertion and stable connectivity with the CPU.

 

Application Fields

S7-400 Automation Systems: The primary application of the Siemens 6ES7952-1AL00-0AA0 is in Siemens S7-400 PLC systems for expanding load memory capacity . It is used in a wide range of industrial automation sectors, including process industry, manufacturing, and infrastructure applications where the S7-400 platform is deployed.

Process Control and PCS 7 Systems: The Siemens 6ES7952-1AL00-0AA0 is recommended for use in PCS 7 process control systems, particularly when online changes to hardware configuration (HCiR) and programs are required without stopping the process . This makes the Siemens 6ES7952-1AL00-0AA0 a vital component for continuous process industries such as chemical, pharmaceutical, and power generation.

High Availability (H) Systems: In redundant S7-400H systems, the Siemens 6ES7952-1AL00-0AA0 provides additional load memory to accommodate the program code and data blocks required for redundant operation . The card supports the memory expansion needs of these critical applications where system reliability is essential.

Legacy System Maintenance and Migration Support: As S7-400 systems continue to operate in plants worldwide, the Siemens 6ES7952-1AL00-0AA0 serves as a crucial spare part for maintenance and repair. While this specific 2 MB variant is a legacy product, it remains essential for supporting existing installations and ensuring long-term system availability in facilities that rely on the S7-400 platform.