Digital electronic modules
3.9 4DI NAMUR digital electronic module (6ES7131-4RD01-0AB0)
ET 200S
3-40
Manual, Edition 10/2005, A5E00514527-01
Value status
The value status provides additional binary information on a digital input signal. The value
status is entered in the process input image at the same time as the signal, and it provides
information on the validity of the input signal. The value status is affected by:
•
Wire break check/short circuit
•
Chatter monitoring
•
Pulse stretching
•
Validity check of changeover contact sensor types
Meaning of the value status:
•
"1": Input signal is valid
•
"0": Input signal is invalid
Assignment in the process input image
The data is transferred to the process image in two bytes (16 bits).
Byte 0
7
6
0
5
4 3 2 1
Byte 1
Input Signal for channel 0
Input Signal for channel 1*
Input Signal for channel 2
Input Signal for channel 3*
Value status for channel 0
Value status for channel 1*
Value status for channel 2
Value status for channel 3*
Meaning
1: Signal valid
0: Signal invalid
unassigned
* Channel not for encoder type changeover contact
Figure 3-10 Assignment in the process input image for 4DI NAMUR