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4 monitoring and editing pc tasks – Rockwell Automation 57C620 AutoMax Programming Executive Version 3.8 User Manual

Page 207

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18Ć19

On Line Menu: Monitoring and Editing Tasks

18.4

Monitoring and Editing PC Tasks

WARNING

USE OF THE ONLINE EDITING FEATURE CAN CAUSE THE CONTROLLED

PROCESS OR MACHINE TO SUDDENLY CHANGE ITS OPERATION. IT IS THE

RESPONSIBILITY OF THE USER TO DETERMINE THE POTENTIAL HAZARDS

INVOLVED. FAILURE TO OBSERVE THESE PRECAUTIONS COULD RESULT IN

BODILY INJURY.

Before you change any Ladder Logic task online, you should be

familiar with the information in 4.22.1, which describes variable types

and naming conventions in AutoMax Ladder Logic tasks.
The Monitor PC menu is used to monitor the state of Ladder Logic

task sequences in realĆtime and - unlike file editing - to modify

individual control logic sequences online while tasks are running.

To make any changes to Ladder Logic tasks, the keyswitch must be

in PROGRAM and the password must be entered.
Online editing operations supported include adding, deleting, and

modifying an existing sequence, modifying the value of a preset,

forcing/unforcing a variable, moving one or a set of sequences, and

resequencing all or part of a task. You can only modify one sequence

(edit one sequence, add one sequence, or delete one sequence) at a

time. Any online changes made take effect during the scan

immediately following the task scan during which the change is

installed.
When you monitor a sequence, the power flow is indicated by

reverse video display for those portions of the sequence that have

electrical continuity. If a sequence contains a timer or counter, the

current value is displayed, along with the preset value. For shift

registers, the current contents of the register are displayed. Variable

names displayed in lowerĆcase indicate local variables. Those

displayed in upperĆcase are common variables. See figure 18.6 for a

sample display.