Displaying And Setting In Engineering Units; Overview - Omron CX-PROCESS TOOL V5.2 - 12-2009 Operation Manual

Displaying and Setting in Engineering Units

3-9

Displaying and Setting in Engineering Units

3-9-1 Overview

Configuration for Engineering Unit Conversion
Downloading
percentage
data
Loop Controller
Conversion Errors
Engineering units can be used to display and set the analog data handled by the
CX-Process Tool. Data is converted to engineering units based on the CSV tag
information set for the function block.
Note This function can be used only with Loop Control Boards, Loop-con-
trol CPU Units, and Process-control CPU Units. It is not supported by
Loop Control Units.
Function
block ITEM
Percentage
data
Uploading
percentage
data
(Configuration for Engineering Unit Conversion)
The above diagram shows the configuration for using the engineering unit dis-
play and setting function to convert Loop Controller parameters into engineering
units.
Engineering units are values that have been converted into the values actually
used for I/O based on scaling of ITEM data handled by the Loop Controller. They
are applicable to values such as temperatures (°C) and voltages (Pa). Con-
versely, the main analog data handled by the Loop Controller (e.g., PV or SP for
basic PID) is expressed in values such as -15.00% to +115% or -320.00% to
+320%. This is called percentage (%) data.
The CX-Process Tool converts function block ITEM displays into engineering
units based on CSV tags set by the user. Displays and settings on the CX-Pro-
cess Tool can use engineering units when the engineering unit display and set-
ting function is enabled, making it possible to check and input values more intu-
itively. (When this function is disabled, or when CSV tags are not set, editing is
only possible for percentage (%) data.)
When the CX-Process Tool exchanges data with the Loop Controller, it is per-
centage (%) data that is transferred. Loop Controller internal processing is
executed using percentage (%) data, so reverse conversion from engineering
units to percentage (%) data is performed automatically when data is trans-
ferred.
The main analog data is processed as percentage data in the Loop Controller.
The maximum resolution for this data is 64,000. Depending on the scaling set-
CX-Process Tool
The user sets the scaling information.
CSV tag
Function
block ITEM
Conversion
Engineering
units
Reverse conversion
Section
User
Monitoring in en-
gineering units
Settings in engi-
neering units
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