About SIMATIC S7-400, digital input SM 421, isolated 32 DI

SIMATIC S7-400 SM 421 Digital Input Module

Part Number: 6ES7421-1BL01-0AA0
Type: Isolated 32 DI, 24 V DC

Input Current

• From backplane bus (5 V DC): max. 20 mA

Power Loss

• Typical: 6 W

Digital Inputs

• Number of digital inputs: 32

• Input characteristic: IEC 61131 Type 1

• Simultaneously controllable inputs: 32

Input Voltage

• Type: DC

• Rated value: 24 V DC

• Signal 0: 30 V DC to +5 V DC

• Signal 1: 13 V DC to 30 V DC

Input Current (per channel)

• Signal 0 (max quiescent current): 1.3 mA

• Signal 1 (typical): 7 mA

Input Delay

• 0 1: min 1.2 ms, max 4.8 ms

• 1 0: min 1.2 ms, max 4.8 ms

Cable Length

• Shielded: max 1000 m

• Unshielded: max 600 m

Encoder Compatibility

• 2-wire sensor: Yes

• Max quiescent current: 1.5 mA

Diagnostics / Status

• Diagnostics function: No

• Status indicator LEDs (green): Yes

Potential Separation

• Between channels: No

• Between channels in groups: Yes, group of 32

• Between channels and backplane bus: Yes

Isolation

• Isolation test: 500 V AC / 707 V DC (type test)

Mechanical Data

• Width: 25 mm

• Height: 290 mm

• Depth: 210 mm

• Weight: approx. 500 g

Technical Details