Rockwell Automation 1746-NI8 SLC 500 Analog Input Modules User Manual - Manual (Page 58)

6–3 Ladder Logic Configuration Examples
Publication 1746Ć6.8 - April 1997
The analog input module was designed to interface directly to the
SLC 5/02
t or later processor PID instruction without the need for
an intermediate scale operation.
Example - Use 1746-NI8 channel data as the process variable in the
PID instruction.
1. Select scaled-for-PID as the data format in the channel
configuration word.
2. Specify the 1746-NI8 channel data word as the process variable
for the PID instruction.
Program Listing
PID
Control Block
N11:0
Process Variable I:3.0
Control Variable N11:23
Control Block Length 23
] [ MOVE
Source
N10:0
3083
Dest O:3.0
0
First Pass Bit
S2:1
15
Channel 0
MOV
Initialize 1746ĆNI8
Channel 0
Status
SCL
Scale
Source
N11:23
?
Rate [/10000] ?
?
Offset ?
?
Dest ?
?
The Rate and Offset parameters should
be set per your application. The Dest
will typically be an analog output
channel. Refer to your programming
device's user manual or Analog I/O
Modules User Manual for specific
examples of the SCL instruction.
END
PID
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
Interfacing to the PID
Instruction