Product Description
Key Features
- Digital input capacity: Has 32 digital inputs, with 32 inputs simultaneously controllable.
- Input voltage: DC input voltage with a rated value of 24 V; signal "0": -30 V DC to +5 V DC, and signal "1": 13 V DC to 30 V DC.
- Input characteristic: Type 1 input characteristic according to IEC 61131.
- Isolation and diagnostics: Digital inputs are isolated from the backplane bus, with no channel-to-channel potential separation and no diagnostics function. A green digital-input status LED is present.
- Cable and sensor connections: Maximum cable length is 1 000 m shielded or 600 m unshielded. A 2-wire sensor is connectable with a maximum permissible quiescent current of 1.5 mA.
Technical Summary
| Product | SIMATIC S7-400, digital input SM 421, isolated 32 DI; 24 V DC |
|---|---|
| Product lifecycle | Announcement of product phase-out |
| Digital inputs | 32 |
| Rated input voltage | 24 V |
| Simultaneously controllable inputs | 32 |
| Input characteristic | Type 1 according to IEC 61131 |
| Signal "0" input voltage | -30 V DC to +5 V DC |
| Signal "1" input voltage | 13 V DC to 30 V DC |
| Backplane bus input current, max. | 20 mA |
| Power loss, typ. | 6 W |
Frequently Asked Questions
What order number should be confirmed for this Siemens module?
Confirm the complete nameplate order number: 6ES7421-1BL01-0AA0.
What input configuration does the module have?
It has 32 isolated digital inputs with a 24 V DC rated input voltage and 32 simultaneously controllable inputs.
Does the module provide diagnostics?
It has no diagnostics function, but it has a green digital-input status LED.
What cable lengths are supported?
The maximum cable length is 1 000 m for shielded cable and 600 m for unshielded cable.
