Rockwell Automation 1746-NR8 SLC 500 RTD/Resistance Input Module User Manual - Manual (Page 67)

Publication 1746-UM003A-EN-P
Channel Configuration, Data, and Status 4-19
Channel Data Word The actual RTD or resistance input sensor values reside in I:e.0 through I:e.7
of the RTD module input image file. The data values present depend on the
input type and data format you have selected in your configuration for the
channel. When an input channel is disabled, its data word is reset (0).
Two conditions must be true for the value of the data word to be valid:
•
The channel must be enabled (channel status bit = 1).
•
There must be no channel errors or channel LED on (channel error bit = 0)
Figure 4.6 Module Input Image (Data Words)
Channel Status Checking The channel status word is a part of the RTD module’s input image. Input
words 8 through 15 (Class 3 only) correspond to and contain the configuration
status of channels 0 through 7 respectively. You can use the data provided in
the status word to determine if the data word for any channel is valid per your
configuration in O:e.0 through O:e.7 or O:e.23 (Class 3 only).
For example, whenever a channel is disabled (O:e.x/11 = 0), its corresponding
status word shows all zeros. This condition tells you that input data contained
in the data word for that channel is not valid and should be ignored.
Channel 0 Data Word
Channel 1 Data Word
Channel 2 Data Word
Channel 3 Data Word
Channel 4 Data Word
Channel 5 Data Word
Channel 6 Data Word
Channel 7 Data Word
I:e.0
I:e.1
I:e.2
I:e.3
I:e.4
I:e.5
I:e.6
I:e.7