Rockwell Automation 1746-NI16V SLC 500 Analog Input Modules User Manual - Manual (Page 42)

Publication 1746-UM001A-US-P
4-6 Preliminary Operating Considerations
channel and provide information about the channel’s operational
state. To receive valid status information, the channel must be
enabled, and the channel must have processed any configuration
changes that may have been made to the configuration word.
Class 1 Input Words - Status
The status words for Class 1 are the input words 0 through 8. Setting
bits 1 and 0 in the output configuration word to 10 or 11 returns status
for channels 0 through 7 or 8 through 15, respectively.
Class 3 Input Words - Status
The status words for Class 1 are the input words 16 through 31. Status
for all 16 channels can be viewed at the same time as data for all 16
channels.
Class 3 Example - To obtain the status of channel 2 (input word 18)
of the analog module located in slot 4 in the SLC chassis, use address
I:4.18.
Chapter 5, Channel Configuration, Data, and Status, gives you
detailed bit information about the content of the data word and the
status word. Also, see Chapter 7 for a detailed explanation and
application examples.
Module Update Time The module update time is defined as the time required for the
module to sample and convert the input signals of all enabled input
channels and provide the resulting data values to the SLC 500
processor. For the most part, the module update time depends on the
filter setting. Lower filter frequencies can be selected to reject noise.
However, as noise rejection improves, module update time increases.
Choose the lowest filter frequency consistent with how quickly your
program requires fresh analog data.
I : 4 . 18
Word
Slot
Word Delimiter
File Type
Element Delimiter