Siemens Simatic S7-400 Reference Manual

4.8 Digital input module SM 421; DI 16 x DC 24 V
(6ES7421-7BH01-0AB0)
4.8.1 Features
Overview
SM 421; DI 16 x 24 V DC has the following properties:
● 16 inputs, isolated in 2 groups of 8
● Rapid signal processing Input filter from 50 µs
● Rated input voltage 24 V DC
● Suitable for switches and 2-/3-/4-wire proximity switches (BEROs, IEC 61131-2; type 2)
● 2 short-circuit proof sensor supplies for 8 channels each
● External redundant supply for sensor supply possible
● Status display "Sensor voltage (Vs) O.K."
● Group fault display for internal faults (INTF) and external faults (EXTF)
● Configurable diagnostics
● Configurable diagnostic interrupt
● Configurable hardware interrupts
● Configurable input delays
● Configurable substitute values in the input range
The status LEDs indicate the process status.
Note
The module spare parts are compatible with SM 421 module; DI 16 x 24 V DC;
(6ES7 421-7BH00-0AB0)
To use the new function "Input delay 50 µs", you require STEP7 from V 5.2.
Digital modules
4.8 Digital input module SM 421; DI 16 x DC 24 V (6ES7421-7BH01-0AB0)
S7-400 Automation System Module Data
100 Reference Manual, Ausgabe 11/2016, A5E00850736-08

Siemens Simatic S7-400 Specifications

General

Programming Language	STEP 7 (LAD, FBD, STL, SCL, GRAPH)
Communication Interfaces	MPI, PROFIBUS
Power Supply	24 V DC, 120/230 V AC (Power supply modules are separate and chosen based on system requirements)
Operating Temperature	0°C to 60°C
Mounting	Rack mounting
Processor	CPU 412-1, CPU 414-2, CPU 416-2, CPU 417-4 (Different CPUs offer varying performance and features)
Relative Humidity	5 to 95% (non-condensing)