4.10.2
Assigning parameters to the SM 421; DI 16 x UC 24/60 V
Parameter assignment
You will find a description of the general configuration of digital modules in section 5.3.
Parameters of the SM 421; DI 16 x UC 24/60 V
The following table contains an overview of the parameters you can set and their default
settings for the SM 421; DI 16 x UC 24/60 V.
Table 4-11
Parameters of the SM 421; DI 16 x UC 24/60 V
Parameters
Value range
Default
2
Parameter type
Scope
Enable
● Diagnostic interrupt
1
Yes/no
No
Dynamic
Module
● Hardware interrupt
1
Yes/no
No
● Destination CPU for interrupt
1 to 4
-
Static
Module
Diagnostics
● Wire break
Yes/no
No
Static
Channel
Hardware interrupt trigger
● Positive edge
● Negative edge
yes/no
yes/no
-
Dynamic
Channel
Input delay
3
0.5 ms (DC)
3 ms (DC)
20 ms (DC/AC)
3 ms (DC)
Static
Channel group
1
If you use the module in ER-1/ER-2, you must set this parameter to "No" because the interrupt lines are not available in
ER-1/ER-2.
2
Only in the CR (central rack) is it possible to start up the digital modules with the default settings.
3
If you assign 0.5 ms , then you should not configure diagnostics because the internal processing time for diagnostic functions
can be > 0.5 ms.
Ensuring a wire break check is carried out
To ensure that a wire break check is carried out, you require an external sensor circuit using
a resistor of 18 to 56 kΩ. The resistor should be connected parallel to the contact and should
be arranged as closely as possible to the sensor.
This additional resistor is not required in the following cases:
● If 2-wire BEROs are used
● If you do no configure the "Wire Break" diagnostics
Digital modules
4.10 Digital input module SM 421; DI 16 x UC 24/60 V (6ES7421-7DH00-0AB0)
S7-400 Automation System Module Data
116
Reference Manual, Ausgabe 11/2016, A5E00850736-08