Spectrum Controls 1746sc-INI4vi - Manual (Page 45)

Chapter 5: Ladder Program Examples 41
User-Defined Scaling Your input module was designed to work directly with applications
requiring special data scaling—without an intermediate scaling
operation.
Example — Suppose your input module is in slot 3, and you have a
pressure sensor with a 4–20 mA range connected to channel 0. The
following figures show you how to use the User-Defined Scaling data
format to send specially scaled data (100 to 9999 in this example) to a
simple display-only operator interface:
Figure 14. User-defined scaling example.
4–20 mA
Pressure
Sensor
CPU
1746sc-INI4i
Analog Input
Module (slot 3)
Simple display-only
Operator Interface
Analog Input Signal (channel 0)
Specially
scaled data
(e.g., 100–9999)
Figure 15. Programming for user-defined scaling example.
Rung 2:0 First Pass Bit
s:1
] [
15 COP
COPY FILE
Source #N10:0
Dest #O:3.0
Length 6
Initialize Module
END
Rung 2:1
Figure 16. Data table for user-defined scaling example.
address 15 data 0 address 15 data 0
N10:0 0000 0000 0100 1011 N10:3 0000 0000 0000 0000
N10:1 0000 0000 0000 0000 N10:4 0000 0000 0110 0100 (100 gallons)
N10:2 0000 0000 0000 0000 N10:5 0010 0111 0000 1111 (9999 gallons)
In this example, the operator interface is programmed to read I:3.0
(channel 0 data word).