Rockwell Automation 1746-NI8 SLC 500 Analog Input Modules User Manual - Manual (Page 59)

6–4 Ladder Logic Configuration Examples
Publication 1746Ć6.8 - April 1997
This example shows how you could monitor the open circuit error
bits of each channel and set an alarm in the processor if one of the
channels opens. An open circuit error can occur if the analog input
device breaks, or one of the sensor wires gets cut or disconnected
from the terminal block.
Program Listing
] [ Copy File
Source
#N10:0
Dest #O:3.0
Length 8
First Pass Bit
S2:1
15
COP
Initialize 1746ĆNI8
11
Channel 0
Status
] [
I:3.8
] [
I:3.8
12
( )
O:2.0
0
Channel 0
Open
Channel 0
Alarm
11
Channel 1
Status
I:3.9
12
( )
O:2.0
1
Channel 1
Open
Channel 1
Alarm
I:3.9
] [ ] [
11
Channel 7
Status
I:3.15
] [
I:3.15
12
( )
O:2.0
7
Channel 7
Open
Channel 7
Alarm
] [
END
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DATA FILE N10
Offset 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
N10:0 0 0 0 0 1 1 0 0 0 0 0 0 1 1 0 1
N10:1 0 0 0 0 1 1 0 0 0 0 0 0 1 1 0 1
N10:2 0 0 0 0 1 1 0 0 0 0 0 0 1 1 0 1
N10:3 0 0 0 0 1 1 0 0 0 0 0 0 1 1 0 1
N10:4 0 0 0 0 1 1 0 0 0 0 0 0 1 1 0 1
N10:5 0 0 0 0 1 1 0 0 0 0 0 0 1 1 0 1
N10:6 0 0 0 0 1 1 0 0 0 0 0 0 1 1 0 1
N10:7 0 0 0 0 1 1 0 0 0 0 0 0 1 1 0 1
Monitoring Channel Status
Bits (Class 3 Mode Only)