Rockwell Automation 1746-NR4 SLC RTD/Resistance Input Module User Manual - Manual (Page 96)

Publication 1746-UM008B-EN-P - December 2006
96 Ladder Programming Examples
Monitor Channel Status
Bits The Programming to Monitor Channel Status ladder diagram shows
how you could monitor the open- and short-circuit error bits of each
channel and set an alarm in the processor if one of the RTDs or
resistance-input devices (such as a potentiometer) opens or shorts. An
open-circuit error can occur if the RTD or resistance-input device
breaks or one of the RTD or resistance-input device wires get cut or
disconnected from the terminal block. A short-circuit condition
applies only to RTD input.
Programming to Monitor Channel Status
] [ COPY FILE
Source
#N10:0
Dest #O:3.0
Length 4
First Pass Bit
S:1
15
Rung 2:0
COP
Initialize RTD module.
11
Rung 2:1 Channel 0
Status
] [
I:3.4
] [
I:3.4
13
( )
O:2.0
0
Channel 0
Open or Short
Channel 0
Alarm
11
Rung 2:2 Channel 1
Status
I:3.5
13
( )
O:2.0
1
Channel 1
Open or Short
Channel 1
Alarm
I:3.5
] [ ] [
11
Rung 2:3 Channel 2
Status
I:3.6 I:3.6
13
( )
O:2.0
2
Channel 2
Open or Short
Channel 2
Alarm
] [ ] [
11
Rung 2:4 Channel 3
Status
I:3.7
] [
I:3.7
13
( )
O:2.0
3
Channel 3
Open or Short
Channel 3
Alarm
] [
Rung 2:5
END