Cable length
● unshielded
600 m
● shielded
1000 m
Voltage, current and potential
● Reverse polarity protection
Yes
Number of inputs that can be enabled simultaneously 32
Electrical isolation
● Between channels and backplane bus
Yes
● Between channels
in groups of
Yes
8
Permissible potential difference
● Between M
intern
and the inputs
120 V AC (reinforced insulation)
● Between inputs of different groups
250 V AC (basic insulation)
Insulation tested at
1500 V AC
Current consumption
● From backplane bus (5 V)
Maximum 200 mA
Module power loss
Typ. 6.5 W
Status, interrupts, diagnostics
Status display
Green LED per channel
Interrupts
None
Diagnostic functions
None
Data for selecting a sensor
Input voltage
● Rated value
UC 120 V
● For "1" signal
79 to 132 V AC
80 to 132 V DC
● For "0" signal
0 to 20 V
● Frequency range
47 to 63 Hz
Input current
● For "1" signal
2 to 5 mA
● For "0" signal
0 to 1 mA
Input delay
● For "0" to "1"
5 to 25 ms
● For "1" to "0"
5 to 25 ms
Input characteristic
In accordance with IEC 61131; type 1
Connection of 2-wire BEROs
Possible
● Permissible quiescent current
Maximum 1 mA
Digital modules
4.13 Digital input module SM 421; DI 32xUC 120 V (6ES7421-1EL00-0AA0)
S7-400 Automation System Module Data
128
Reference Manual, Ausgabe 11/2016, A5E00850736-08