Siemens 6ES5374-2FJ21 Memory Card for SIMATIC S5 Systems

The Siemens 6ES5374-2FJ21 provides portable program storage for SIMATIC S5 PLCs. You can insert this card into any standard S5 memory slot. It holds user logic and configuration data without an internal battery. This accessory suits program backups and controller replacements.

Technical Specifications and Physical Design

This memory card measures 98 mm in height. Its width reaches 48 mm, and the depth equals 8 mm. The Siemens 6ES5374-2FJ21 weighs approximately 0.05 kilograms. A single internal PCB holds all EEPROM memory components. The card contains no energy storage capacitors or batteries. It retains data for over ten years without any power source. One 40-pin edge connector interfaces with the S5 backplane. A write-protect slider sits on the card’s front edge.

Memory Capacity and Compatibility

The Siemens 6ES5374-2FJ21 provides 16 KB of user program storage. This capacity handles approximately 1500 ladder logic instructions comfortably. The EEPROM technology allows 100,000 write cycles minimum. Consequently, this card supports frequent program changes without wear concerns. The module works with all S5 CPU models including 115U, 135U, and 155U. You can store multiple program versions on different cards easily.

Installation and Practical Usage Guidelines

You must insert this card firmly into the S5 memory slot. Transitioning to programming, use an S5 programmer to write the logic. The write-protect slider prevents accidental program overwrites. Always power off the PLC before inserting or removing the card. For safe storage, keep the card in its anti-static sleeve. The operating temperature range spans from -20°C to +70°C reliably.