Digital Modules
4-15
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
4.6
Input Characteristic Curve for Digital Inputs
IEC 61131, Type 1 and Type 2
The IEC 61131 standard requires the following for the input current:
•
In the case of type 2, an input current of
y
2 mA already at + 5 V
•
In the case of type 1, an input current of
y
0.5 mA already at + 5 V
EN 60947-5-2, Two-Wire BEROs
The standard for BEROs (EN 60947-5-2) specifies that there can be a current of
v
1.5 mA for BEROs in the “0” signal state.
The input current of the module in the ”0” signal state is decisive for the operation
of two-wire BEROs. This must be in accordance with BERO requirements.
