Product Overview
Applications
Supports wire-break monitoring with a fixed current limitation of 10 kΩ to 18 kΩ and wire-break diagnosis at I < 1 mA.
Technical Summary
| Product | 6ES7421-7BH01-0AB0 |
|---|---|
| Module type | SIMATIC S7-400 SM 421 digital input module |
| Digital inputs | 16 isolated DI; all 16 simultaneously controllable |
| Rated input voltage | 24 V DC |
| Input signal ranges | Signal "0": -30 V DC to +5 V DC; signal "1": 11 V DC to 30 V DC |
| Input frequency, max. | 2 kHz, with a time delay of 0.1 ms |
| Load voltage range | 20.4 V to 28.8 V DC |
| Encoder-supply outputs | 2; L+ (-2.5 V); electronic short-circuit protection |
| Diagnostics | Parameterizable diagnostics, diagnostic alarm, hardware interrupt and wire-break diagnosis at I < 1 mA |
Key Features
The SM 421 has 16 digital inputs, with all 16 inputs simultaneously controllable and input characteristic Type 2 according to IEC 61131.
Rated input voltage is 24 V DC. Signal "0" is -30 V DC to +5 V DC, and signal "1" is 11 V DC to 30 V DC.
Parameterizable diagnostics, diagnostic alarms and hardware interrupts are supported. Wire-break diagnosis is available at I < 1 mA.
The module has 2 encoder-supply outputs with output voltage L+ (-2.5 V), electronic short-circuit protection and possible additional redundant feed.
Digital inputs are electrically separated between channels in groups of 8 and from the backplane bus. Isolation is tested with 500 V DC.
Product lifecycle status: Announcement of product phase-out.
Frequently Asked Questions
What exact product is this digital input module?
It is Siemens 6ES7421-7BH01-0AB0, a SIMATIC S7-400 SM 421 digital input module with 16 isolated DI.
What input voltage and signal ranges does it use?
The rated input voltage is 24 V DC. Signal "0" is -30 V DC to +5 V DC, and signal "1" is 11 V DC to 30 V DC.
What diagnostics and interrupt functions are supported?
It has parameterizable diagnostics, diagnostic alarms, hardware interrupts, readable diagnostic information, supply-voltage monitoring and wire-break diagnosis at I < 1 mA.
How is the input module configured for a quotation request?
Provide the requested quantity, destination, schedule context and any additional BOM lines for the exact 6ES7421-7BH01-0AB0 line item.
