• Siemens 6ES5921-3UA12
  • Siemens 6ES5921-3UA12
  • Siemens 6ES5921-3UA12
1 3

Siemens 6ES5921-3UA12 SIMATIC S5 CPU Module

Siemens 6ES5921-3UA12 SIMATIC S5 CPU Module

Description

The Siemens 6ES5921-3UA12 is a central processing unit designed for the legacy SIMATIC S5 programmable logic controller (PLC) platform. This module serves as the primary logic engine for industrial automation...

22 people are viewing this right now

Availability: Low stock: 7 left

SKU: 6ES5921-3UA12
Vendor: Siemens
Category: PLC CPU Module
Related Series:

Shipping & Returns

Reliable Worldwide Delivery

  • Carriers: Shipped via DHL, FedEx, UPS, or USPS.
  • Dispatch: Orders processed in 1-2 business days and dispatched within 3-5 business days.
  • Tracking: Full tracking details provided via email upon shipment.

30-Day Money-Back Guarantee

  • Guarantee: 30-day return window for in-stock, factory-sealed products.
  • Condition: Items must be unopened, unused, and in original packaging.
  • Authenticity: We guarantee 100% original and authentic hardware.

Need more details? Read our fullShipping PolicyandRefund Policy.

Authenticity & Warranty

  • Genuine Guarantee: We supply only 100% original, brand-new, and factory-sealed industrial automation parts.
  • Full Coverage: Every component is backed by a 12-month comprehensive warranty from the date of purchase.
  • Traceability: All products come with original factory documentation and accessories for full industrial compliance.

Technical Support & Sourcing

  • Expert Assistance: Our technical team provides free consultation to help you verify compatibility for DCS and PLC systems.
  • Rare Part Sourcing: Specializing in obsolete and hard-to-find components from Allen-Bradley, Siemens, ABB, HIMA, and more.
  • Bulk Inquiries: Contact us at pambo@5gplc.com for volume pricing or customized project quotes.
View full product details

Description

The Siemens 6ES5921-3UA12 is a central processing unit designed for the legacy SIMATIC S5 programmable logic controller (PLC) platform. This module serves as the primary logic engine for industrial automation systems, managing complex discrete and analog control sequences. It is engineered to provide deterministic scan times and reliable execution of control logic in demanding environments, including heavy manufacturing, petrochemical processing, and metal smelting facilities.

Features

  • Memory Configuration: Equipped with 64 KB of internal RAM for program instruction execution and a dedicated 7.4 KB of RAM specifically for data block (DB) management.
  • Storage Expansion: Features an integrated interface slot compatible with EPROM 921 storage modules, facilitating firmware backup and non-volatile memory retention during power loss.
  • System Integration: Designed for seamless operation within the standard S5 backplane architecture, coordinating data exchange across connected digital and analog I/O modules.
  • Operational Stability: Built to maintain consistent performance under continuous load cycles, reducing the risk of system coordination errors.

Applications

This CPU module is suitable for legacy automation systems requiring reliable, cyclic logic control. It is commonly deployed in infrastructure and industrial utilities where S5-based control architectures remain in operation, providing the necessary processing power for process monitoring and machine sequence management.

Technical Specifications

Model 6ES5921-3UA12
Brand Siemens
Series SIMATIC S5
Program RAM 64 KB
Data Block RAM 7.4 KB
Operating Temperature 0 to 55 deg C
Power Supply Standard S5 Backplane Bus

Installation Guidelines

  • Power Down: Always disconnect power from the S5 rack before inserting or removing the CPU module to prevent electrical damage.
  • Handling: This module contains sensitive electronic components; use proper ESD (electrostatic discharge) protection during handling and installation.
  • Seating: Ensure the module is fully seated in the designated CPU slot of the S5 rack and that the locking mechanism is engaged to maintain backplane connectivity.
  • Environment: Install in a clean, dry environment within the specified temperature range to ensure long-term operational reliability.
  • Cable Routing: Keep communication and I/O signal cables separated from high-voltage power lines to minimize electromagnetic interference (EMI).

FAQ

Is this module compatible with all S5 racks?

The 6ES5921-3UA12 is designed for the standard SIMATIC S5 architecture. Please verify your specific rack configuration and backplane requirements before installation.

Does this module require an external backup battery?

The module supports EPROM 921 storage for non-volatile memory. Ensure your system configuration is correctly set up for the specific memory type being used to prevent data loss during power cycles.