Rockwell Automation 1746-INT4 Thermocouple/MV Isolated/ User Manual - Manual (Page 61)

Publication 1746-UM614B-EN-P - September 2007
Ladder Programming Examples 61
Verify Changes to a
Channel Configuration When changing a channel configuration, there is always a delay until
the ladder logic reads the new data word based on the new
configuration. Therefore, it is important to verify that the module
successfully stored the new channel configuration word. The
following example explains how to verify a change to a channel
configuration.
We do this by adding rung 2:3 to the rungs in the previous example.
Program
EXAMPLE
Change the channel configuration word and verify the change
by comparing the resulting status word with the configuration
word for equality.
] [
COP
COPY FILE
Source
#N10:0
Dest #O:3.0
Length 4
S:1
15
] [
0
B3
0
I:1.0
[OSR]
MOVE
Source
N10:4
Dest O:3.2
MOV
B3
1
]/[ MOVE
Source
N10:2
Dest O:3.2
MOV
0
I:1.0
[OSR]
EQUAL
Source A
I:3.6
Source B O:3.2
EQU
( )
B3
3
END
Rung 2:0 Set up all four channels
Set channel 2 to CJC
Set channel 2 back to Type K
Rung 2:1
Rung 2:2
Rung 2:3
Rung 2:4
Check that the configuration written to channel 2
is being echoed back in channel 2’s status word.
Data valid