Product Overview

The Siemens 6ES7221-1BH22-0XA0 is a SIMATIC S7-200 EM 221 expansion module that adds sixteen 24 V DC digital inputs to compatible S7-22X CPU stations. The inputs support sink/source wiring and are organized in four groups of four.

Official Siemens S7-200 documentation defines the electrical limits, input delay, isolation and cable distances for this exact order number. The model also appears in Siemens' official S7-200 product cancellation list, so replacement projects should verify the complete MLFB and installed CPU configuration.

Commercial Status

Verified Technical Data

System Fit and Applications

Compatibility and Procurement Checks

• Confirm the complete order number 6ES7221-1BH22-0XA0; EM 221 versions differ in channel count and electrical design.
• Verify that the installed controller is a compatible SIMATIC S7-22X CPU and has available expansion capacity.
• Check 24 V DC sink/source wiring, four-group commons, sensor current and the official signal thresholds.
• Keep field cable lengths within the official limits: up to 500 m shielded or 300 m unshielded.
• Because Siemens lists the exact MLFB under Product Cancellation, confirm spare strategy, condition and replacement planning before purchase.

Lifecycle Note

The exact MLFB 6ES7221-1BH22-0XA0 appears in Siemens’ official S7-200 product cancellation list. The lifecycle wording used here is therefore Product Cancellation. Procurement should focus on exact-order verification, installed S7-200 compatibility and a documented spare or modernization strategy.

Frequently Asked Questions