Siemens SIMATIC S7-1200 SB 1221 Digital Input Signal Board, 8x 24 V DC, 100 kHz

The Siemens SIMATIC S7-1200 SB 1221 is a high-performance digital input signal board designed for the SIMATIC S7-1200 controller system. It provides 8 digital inputs with 24 V DC, supporting high-speed counting up to 100 kHz for four inputs. This signal board is ideal for applications requiring precise input capture and fast response times.

Advantages

Compact design directly plugs into the S7-1200 CPU, saving space and simplifying wiring. Configurable input delay from 0.2 ms to 12.8 ms allows adaptation to various signal conditions. LED status indicators for each input enable quick diagnostics.

Suitable for

• Industrial automation and control systems
• High-speed counting and frequency measurement
• Machine monitoring and sensor integration

Key specifications

• Product Type: Signal Board
• Series: SIMATIC S7-1200
• Number of Digital Inputs: 8
• Input Voltage: 24 V DC
• Input Current (for signal 1): 2.5 mA
• Input Delay (configurable): 0.2 ms to 12.8 ms
• High-Speed Counter Frequency: Up to 100 kHz (for 4 inputs)
• Input Type: Type 1 (IEC 61131-2)
• Isolation: Functional isolation from backplane bus
• Mounting Type: Direct plug-in on SIMATIC S7-1200 CPU
• Compatible CPUs: SIMATIC S7-1200 CPUs
• Power Consumption: Max. 1 W (from backplane bus)
• Operating Temperature: -20 °C to +60 °C (horizontal mounting)
• Connection Type: Screw terminals
• Status Indicators: 8x LED for input status
• Max. Cable Length (shielded): 500 m
• Max. Cable Length (unshielded): 150 m

Recommendations

For optimal performance, use shielded cables in high-noise environments. Ensure proper mounting orientation to maintain temperature specifications.