Product Description
Key Features
- Isolated digital input capacity: The SM 421 has 32 digital inputs, with 32 inputs simultaneously controllable.
- 120 V AC/DC input: Input voltage is AC/DC, with a rated value of 120 V at 47 … 63 Hz.
- Input characteristics: The inputs have an IEC 61131 Type 1 characteristic; signal "0" is 0 to 20 V UC and signal "1" is 79 to 132 V AC or 80 to 132 V DC.
- Electrical separation: Digital inputs are electrically separated between channels and between channels and the backplane bus; separation is in groups of 8.
- Installation dimensions: The module measures 25 mm wide, 290 mm high, and 210 mm deep, with an approximate weight of 600 g.
- Product lifecycle: The product has an Announcement of product phase-out.
Technical Summary
| Product identity | SIMATIC S7-400, digital input SM 421, isolated 32 DI; 120 V DC/AC |
|---|---|
| Order number | 6ES7421-1EL00-0AA0 |
| Digital inputs | 32 |
| Simultaneously controllable inputs | 32 |
| Rated input voltage | 120 V; 47 … 63 Hz |
| Input voltage type | AC/DC |
| Input characteristic | IEC 61131 Type 1 |
| Signal "0" input voltage | 0 to 20 V UC |
| Signal "1" input voltage | 79 to 132 V AC; 80 to 132 V DC |
| Backplane bus input current | 200 mA from backplane bus 5 V DC, max. |
| Power loss | 6.5 W, typ. |
Frequently Asked Questions
What exact order number should be confirmed for this Siemens module?
The exact order number is 6ES7421-1EL00-0AA0.
How many digital inputs does the module provide?
It provides 32 digital inputs, with 32 inputs simultaneously controllable.
What input supply and signal ranges should be checked?
The input is AC/DC with a rated value of 120 V at 47 … 63 Hz. Signal "0" is 0 to 20 V UC, while signal "1" is 79 to 132 V AC or 80 to 132 V DC.
