Siemens SIMATIC S7-400 Reference Manual page 124

Digital modules
4.12 Digital input module SM 421; DI 16 x UC 120/230 V (6ES7421-1FH20-0AA0)
● shielded
Rated supply voltage of electronics L+
Number of inputs that can be enabled simultaneously
Electrical isolation
● Between channels and backplane bus
● Between channels
Permissible potential difference
● Between M
● Between inputs of different groups
Current consumption
● From backplane bus (5 V)
Module power loss
Status display
Interrupts
Diagnostic functions
Substitute values can be connected
Input voltage
● Rated value
● For "1" signal
● For "0" signal
Frequency range
Input current
● For "1" signal (120 V)
● For "1" signal (230 V)
● For "0" signal
Input delay
● For "0" to "1"
124
in groups of
and the inputs
intern
1000 m
Voltage, current and potential
None
16
Yes
Yes
4
250 V AC (reinforced insulation)
Test voltage:
4000 Vac (type test)
2400 AC (routine test)
500 V AC (basic insulation)
Test voltage:
2400 Vac (routine test)
2300 Vac (type test)
Maximum 80 mA
Typ. 12 W
Status, interrupts, diagnostics
Green LED per channel
None
None
No
Data for selecting a sensor
UC 120/230 V
74 to 264 V AC
80 to 264 V DC
-80 to -264 V DC
0 to 40 V AC
-40 to +40 V DC
47 to 63 Hz
Typ. 10 mA AC
Typ. 1.8 mA DC
Typ. 14 mA AC
Typ. 2 mA DC
0 to 6 mA AC
0 to 2 mA DC
Maximum 20 ms AC
Maximum 15 ms DC
Reference Manual, Ausgabe 11/2016, A5E00850736-08
S7-400 Automation System Module Data