Interfacing to the pid instruction, Interfacing to the pid instruction -5 – Rockwell Automation 1746-NT4 Series B,D17466.6.1 SLC 500 4-Channel Thermocouple/mV Input Module User Manual User Manual
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Publication 1746-UM007C-EN-P - July 2004
Ladder Programming Examples 6-5
Interfacing to the PID
Instruction
The thermocouple module was designed to interface directly to the
SLC 5/02 or later processor PID instruction without the need for an
intermediate scale operation.
Example - Use NT4 channel data as the process variable in the PID
instruction.
1. Select scaled-for-PID as the data type in the channel
configuration word.
2. Specify the thermocouple 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 Length23
] [
MOVE
Source N10:0
2081
Dest
O:3.0
0
First Pass Bit
S:1
15
Channel 0
Rung 2:0
MOV
Initialize NT4
11
Rung 2:1
Channel 0
Status
] [
I:3.4
Rung 2:2
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 chan-
nel. Refer to your programming device's
user manual or Analog I/O Modules
User Manual for specific examples of
the SCL instruction.
Rung 2:3
END
PID
Data Table
address 15 data 0 address 15 data 0
N10:0 0000 1000 0010 0001