Digital Modules
4-43
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
Technical Specifications of the SM 421; DI 16 120 VAC
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
Isolation
• Between channels and
backplane bus
Yes
• Between the channels Yes
– In groups of 1
Permitted potential difference
• Between M
internal
and the
inputs
120 VAC
• Between the inputs of the
different groups
250 VAC
Insulation tested with 1500 VAC
Current consumption
• From the backplane bus Max. 0.1 A
Power dissipation of the
module
Typ. 3.0 W
Status, Interrupts, Diagnostics
Status display Green LED per
channel
Interrupts None
Diagnostic functions None
Sensor Selection Data
Input voltage
• Rated value
• For signal “1”
• For signal “0”
• Frequency range
120 V
72 to 132 VAC
0 to 20 V
47 to 63 Hz
Input current
• At signal “1”
• At signal “0”
6 to 20 mA
0 to 4 mA
Input delay
• At “0” to “1”
• At “1” to “0”
2 to 15 ms
5 to 25 ms
Input characteristic curve To IEC 61131; type 2
Connection of two-wire BEROs
• Permitted bias current
Possible
Max. 4 A