Reliable digital input module 6ES7221‑1BH32‑0XB0 for SIMATIC S7‑1200 systems
The Siemens 6ES7221‑1BH32‑0XB0 is a digital input module from the SIMATIC S7‑1200 family, known as SM 1221. It provides 16 digital inputs designed for 24 V DC operation and supports both sink and source wiring. This module is ideal for expanding your PLC’s input capacity in compact automation systems, all while maintaining signal reliability and full integration with Siemens hardware and software.
Technical specifications
-
Manufacturer: Siemens
-
Series: SM 1221 digital input modules
-
Inputs: 16 digital (24 V DC, sink/source)
-
Input voltage range: 20.4 – 28.8 V DC
-
Protection: IP20 (housing)
-
Dimensions: approx. 45 mm × 100 mm × 75 mm
-
Weight: approx. 210 g
-
Mounting: DIN rail via modular S7‑1200 backplane
-
Operating temperature: –20 °C to +60 °C
-
Certifications: CE, UL, CSA
Key advantages
-
Expands PLC input capacity in a compact module
-
Supports both sink and source wiring for flexibility
-
Seamless integration with Siemens S7‑1200 and TIA Portal
-
Reliable signal processing in industrial environments
-
Compact dimensions and lightweight design
Application and use cases of 6ES7221‑1BH32‑0XB0
This module is commonly used to add digital input capability to SIMATIC S7‑1200 systems in areas such as machinery control, packaging lines, factory automation, and process systems. It’s especially suitable where space is limited but reliable I/O expansion is needed.
About the manufacturer
Siemens is a global leader in industrial automation and digitalization. The SIMATIC family, including the S7‑1200 line and SM expansion modules, delivers scalable and modular control solutions trusted in diverse industrial sectors.