Siemens SIMATIC ET 200X, Manual

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Commissioning and Diagnostics
5-4
ET 200X Distributed I/O Device
EWA 4NEB 780601602-06
Signals (user data) and diagnostics data are mutually independent. The
diagnostics input merely shows the state of the sensor or actuator; there is no
defined effect on the signal. The necessary or desired reaction can only be derived
from the application.
The examples below illustrate the relationship between the individual signals and
the diagnostic inputs.
Bit assignment of the inputs
In the PI, inputs are assigned as shown in Figure 5-2.
7 6 5 4 3 2 1 0 Bit
Byte 0 ND7 ND6 ND5 ND4 ND3 ND2 ND1 ND0
Byte 1 FI7 FI6 FI5 FI4 FI3 FI2 FI1 FI0
ND0 ... ND7: Signal (user datum, digital)
channel 0 to channel 7
FI0 ... FI7: Functional input (diagnostics datum)
channel 0 to channel 7
Each functional input can be parameterized
– as a diagnostics input or
– as an input with NC function.
Default: diagnostic input
Figure 5-2 Assignment of the inputs in the process image (PI)
Bit assignment of the outputs
In the PI, outputs are assigned as shown in Figure 5-3.
7 6 5 4 3 2 1 0 Bit
Byte 0 ND7 ND6 ND5 ND4 ND3 ND2 ND1 ND0
Byte 1 0
ND0 ... ND7: Signal (user datum, digital)
channel 0 to channel 7
Byte 1 is not used (= 0)
0 0 0 0 0 0 0
Figure 5-3 Assignment of the outputs in the process image (PI)