Digital Modules
4-22
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
Technical Specifications of the
SM 421; DI 32 x 24 VDC
Dimensions and Weight
Dimensions W
H
D
(in millimeters)
25
290
210
Weight
Approx. 500 g
Data for Specific Module
Number of inputs
32
Length of cable
•
Unshielded
•
Shielded
Max. 600 m
Max. 1000 m
Voltages, Currents, Potentials
Power rated voltage of the
electronics L+
Not required
Number of inputs that can be
triggered simultaneously
32
Isolation
•
Between channels and
backplane bus
Yes
•
Between the channels
No
Permitted potential difference
•
Between the different
circuits
75 VDC / 60 VAC
Insulation tested with
•
Channels against
backplane bus and load
voltage L+
500 VDC
Current consumption
•
From the backplane bus
Max. 20 mA
Power dissipation of the
module
Typ. 6 W
Status, Interrupts, Diagnostics
Status display
Green LED per
channel
Interrupts
None
Diagnostic functions
None
Substitute value can be applied
No
Data for Selecting a Sensor
Input voltage
•
Rated value
•
For signal “1”
•
For signal “0”
24 VDC
13 V to 30 V
-30 V to 5 V
Input current
•
At signal “1”
7 mA
Input delay
•
At “0” to “1”
•
At “1” to “0”
1.2 ms to 4.8 ms
1.2 ms to 4.8 ms
Input characteristic curve
To IEC 61131; type 1
Connection of two-wire BEROs
Possible
•
Permitted bias current
Max. 1.5 mA