PLC | Siemens | 6ES7221-1BH32-0XB0 S7-1200 Digital input SM 1221 6ES7 221-1BH32-0XB0

Product Description: Siemens 6ES7221-1BH32-0XB0

The Siemens 6ES7221-1BH32-0XB0 is a digital input module from the SIMATIC S7-1200 series, designed to provide additional digital input capacity for S7-1200 PLC systems. With 8 input channels, it supports both sink and source wiring configurations, offering high flexibility and compatibility with a wide range of industrial sensors. This compact and robust module ensures fast and accurate signal acquisition in modern automation systems.

Key Features

• 8 digital input channels
• Rated input voltage: 24 V DC
• Supports both sink and source input wiring
• Fast signal processing and short delay times
• Diagnostic LED indicators per channel
• Seamless integration into S7-1200 PLC systems
• Compact design for space-saving installations

Technical Specifications

• Part Number: 6ES7221-1BH32-0XB0
• Number of Inputs: 8
• Input Voltage: 24 V DC
• Input Type: Sink/Source
• Input Current: Approx. 3 mA per channel
• Signal Delay: ≤ 3 ms
• Isolation: None (common ground for all inputs)
• Power Supply: Via backplane bus from the CPU
• Mounting Method: DIN rail
• Dimensions (W × H × D): 45 mm × 100 mm × 75 mm
• Weight: Approx. 150 g
• Operating Temperature: 0 °C to +55 °C
• Storage Temperature: –40 °C to +70 °C
• Protection Class: IP20
• Certifications: CE, cULus

Application Areas

• Sensor signal acquisition in automation systems
• Industrial machinery and equipment monitoring
• Distributed control systems based on S7-1200 architecture
• Small- to mid-size automation tasks requiring modular expansion
• Applications needing reliable 24 V DC digital input processing

Advantages

• Provides easy expansion of digital input capacity
• Supports flexible wiring schemes (sink/source)
• Compact footprint reduces panel space requirements
• Compatible with TIA Portal for quick configuration
• Reliable performance in industrial automation environments