Siemens 6ES7951-0AG00-0AA0 S7-300 RAM Card

Reliable Load Memory Expansion for S7-300 PLCs

The Siemens 6ES7951-0AG00-0AA0 provides a 128 KB RAM memory card for the SIMATIC S7-300 PLC system. This short-version memory card serves as external load memory for user programs and system data . The card plugs directly into the designated CPU slot for seamless integration. Its RAM-based design, operating on 5V Flash EPROM technology, supports fast data access during system operation .

Key Technical Specifications

Parameter	Specification
Product Model	Siemens 6ES7951-0AG00-0AA0
Brand	Siemens
Category	PLC Memory Card (RAM)
Product Family	SIMATIC S7
Memory Type	RAM (5V Flash EPROM)
Memory Size	128 KB
Version	Short Version
Data Width	8 Bit
Compatibility	S7-300 series CPUs
Weight	Approx. 0.01 kg
Country of Origin	Germany

Memory Function and System Operation

The Siemens 6ES7951-0AG00-0AA0 expands the CPU’s load memory capacity for larger program storage. The CPU copies the program from this card into its internal RAM for execution. The card relies on the CPU’s backup battery for data retention. This design ensures fast program load times during system startup.

Physical Design and Installation

Users insert the memory card into the designated slot on the CPU front panel. The short-version format ensures compatibility with all S7-300 CPU models. The lightweight construction of approximately 0.01 kg facilitates easy handling during installation.

Compatibility and System Integration

The Siemens 6ES7951-0AG00-0AA0 integrates with S7-300 CPUs that support external load memory expansion. System compatibility depends on the specific CPU model and firmware version. Users should verify compatibility with their CPU before installation. For new S7-300 systems, Siemens recommends using the equivalent MMC memory cards, such as the 6ES7953-8LG31-0AA0 .