Siemens Industrial Automation

6ES7421-7BH01-0AB0

Siemens 6ES7421-7BH01-0AB0 SIMATIC S7-400 SM 421 digital input module with isolated 16 DI, 24 V DC, 0.05 ms input delay alarm and diagnostics. Check a legacy-part inquiry.

Complete Product Information
Product Code
6ES7421-7BH01-0AB0
Dimensions
29.5 × 23.3 × 3.8 cm
Weight
0.776 kg
Lifecycle
Announcement of product phase-out
Availability
Check availability with quotation
Lead Time
Confirmed with quotation
Product Attachment
Download technical file

Availability, lead time, condition and warranty are confirmed for each quotation.

Product Information

Technical Product Information

Product Description

Key Features

  • Exact module identity: SIMATIC S7-400 digital input SM 421 with isolated 16 DI and a product phase-out announcement.
  • Digital input capacity: 16 digital inputs; all 16 inputs can be controlled simultaneously. Input characteristic according to IEC 61131: Type 2.
  • Input voltage: 24 V DC rated input voltage; signal "0": -30 V DC to +5 V DC; signal "1": 11 V DC to 30 V DC.
  • Supply and protection: Load voltage: 24 V rated, with a permissible range of 20.4 V to 28.8 V DC and reverse polarity protection.
  • Diagnostics and alarms: Parameterizable diagnostics, diagnostic alarm, hardware interrupt, supply-voltage monitoring, and wire-break detection with I < 1 mA.
  • Installation and isolation: Width: 25 mm; height: 290 mm; depth: 210 mm; isolation tested with 500 V DC. Digital inputs are potential-separated in groups of 8.

Applications

  • Digital signal acquisition: Acquires digital input signals through 16 isolated digital inputs.
  • Input diagnostics: Provides parameterizable diagnostics, diagnostic alarms, hardware interrupts, supply-voltage monitoring, and wire-break detection.

Technical Summary

Product 6ES7421-7BH01-0AB0
Module SIMATIC S7-400, digital input SM 421, isolated 16 DI
Product lifecycle Announcement of product phase-out
Rated input voltage 24 V DC
Digital inputs 16
Input characteristic Type 2 according to IEC 61131
Simultaneously controllable inputs 16
Input frequency, max. 2 kHz
Diagnostics Parameterizable diagnostics, diagnostic alarm, hardware interrupt, supply-voltage monitoring, and wire-break detection

Frequently Asked Questions

What is the exact order number of this SM 421 module?

The exact order number is 6ES7421-7BH01-0AB0.

How many digital inputs does the module have?

It has 16 isolated digital inputs, and all 16 can be controlled simultaneously.

What input voltage does the module 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.

Which diagnostics functions are available?

Parameterizable diagnostics, diagnostic alarms, hardware interrupts, readable diagnostic information, supply-voltage monitoring, and wire-break detection are available.

Product Information

RFQ Information

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03What helps with replacement requests?

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