Digital Modules
4-52 S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
Technical Specifications of the SM 421; DI 16 120/230 VUC
Programming package
Associated programming
package As of STEP 7 V 2.0
Dimensions and Weight
Dimensions W H D
(in millimeters) 25 290 210
Weight Approx. 650 g
Data for Specific Module
Number of inputs 16
Length of cable
•Unshielded
•Shielded
600 m
1000 m
Voltages, Currents, Potentials
Number of inputs that can be
triggered simultaneously 16 at 120 V
8 at 240 V
16 with fan
subassembly
Isolation
•Between channels and
backplane bus Yes
•Between the channels Yes
– In groups of 4
Permitted potential difference
•Between Minternal and the
inputs 230 VAC
•Between the inputs of the
different groups 500 VAC
Insulation resistance 4000 VAC
Current consumption
•From the backplane bus Max. 0.1 A
Power dissipation of the
module Typ. 3.5 W
Status, Interrupts, Diagnostics
Status display Green LED per
channel
Interrupts None
Diagnostic functions None
Data for Selecting a Sensor
Input voltage
•Rated value
•For signal “1”
•For signal “0”
120/230 VUC
79 to 264 VAC
80 to 264 VDC
0 VUC to 40 VUC
•Frequency range 47 to 63 Hz
Input current
•At signal “1”
•At signal “0”
2 mA to 5 mA
0 to 1 mA
Input delay
•At “0” to “1”
•At “1” to “0”
5 to 25 ms
5 to 25 ms
Input characteristic curve To IEC 61131; type 1
Connection of two-wire BEROs
•Permitted bias current
Possible
Max. 1 mA