5 forcing variables – Rockwell Automation 57C650 AutoMax Programming Executive Version 3.8 User Manual

Page 217

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18Ć29

On Line Menu: Monitoring and Editing Tasks

18.5

Forcing Variables

WARNING

THE SET AND FORCE FUNCTIONS BYPASS CONTROL OF THE APPLICATION

PROCESS BY THE APPLICATION TASKS. IT IS THE RESPONSIBILITY OF THE

USER TO DETERMINE THE POTENTIAL HAZARDS INVOLVED. FAILURE TO

OBSERVE THESE PRECAUTIONS COULD RESULT IN BODILY INJURY.

WARNING

VARIABLES AND OUTPUTS WHICH ARE FORCED BEFORE AC POWER IS LOST

WILL REMAIN FORCED WHEN AC POWER IS RESTORED. SHOULD AC POWER

BE LOST WHILE VARIABLES ARE FORCED, THE USER MUST ENSURE THAT

UNEXPECTED MACHINE MOVEMENT DOES NOT OCCUR WHEN AC POWER IS

RESTORED. FAILURE TO OBSERVE THESE PRECAUTIONS COULD RESULT IN

BODILY INJURY.

From the Monitor menu shown in figure 18.1, you can select F" for

Force to force and unforce up to 16 variables at the same time. Note

that the limit of 16 forced variables applies regardless of the number

of users who have access to the tack. You can only force boolean,

single precision integer, double precision integer, and real variables.

Strings, array elements, and tunable variables cannot not be forced.

A variable that is forced cannot be altered by any application task or

the status of physical I/O. A forced variable will retain its forced value

until it is unforced or forced to a different value.
See 18.5.1 for an explanation of the screen display and 18.5.2 and

18.5.3 for instructions on forcing and unforcing variables.

18.5.1

Monitor Force Screen Display

Forced variables are displayed in a table on the screen. The columns

in the force table contain the following information:

(#)

Ć Force table (screen) position (1Ć16).

Task

Ć The task in which the variable is defined. This field

is blank if the variable is COMMON.

Variable

Ć Name of the variable being forced, including the

type character.

Value

Ć The current forced value of the variable.

See figure 18.7 for a the Monitor Force menu.

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