Rockwell-automation Logix5000 Controllers I/O and Tag Data Programming Manual de usuario descargar pdf (Pagina 81)

Data access control Chapter 4

Dialog Box/Window Considerations

Tag Monitor You can change the value of a constant tag in the Tag Monitor if you have both standard Tag: Modify Values permission and Tag: Modify Constant

Tag Values permission. You cannot change a constant value in any of the language editors or any other tag browser. The icon in the Value

column indicates that you are changing a constant value tag’s value. Any change to the values of a constant tag is recorded in the Controller Log for

future reference.

For controller logging, see the Logix5000 Controllers Information and Status Programming Manual, publication 1756-PM015

(4) If the controller is in safety-locked mode, only the safety tags are unavailable, and the standard tags will have the same behavior as

in the unlocked mode. The Constant check box is unavailable in the Tag Properties dialog box only if the tag is a safety tag.

The Constant attribute applies only to InOut parameters. The default setting of

the property is not a Constant Value.

The Constant attribute does not apply to Input, Output, EnableIn and

EnableOut Add-On Instruction parameters. It does not apply to Add-On

Instruction Local tags.

If in an Add-On Instruction, you make an InOut parameter a constant, it means

that within the Add-On Instruction, nothing can write to that parameter. The

project fails verification if this type of write is attempted.

Appropriate usage of Constant tags is monitored by logic verification.

Add-on instructions

constant value

considerations

Rock well Automati on Publication 1756- PM004E -EN-P - October 2014 81

1 2 ... 76 77 78 79 80 81 82 83 84 85 86

Comentarios a estos manuales

Sin comentarios

Rockwell-automation Logix5000 Controllers I/O and Tag Data Programming Manual de usuario Pagina 81

Comentarios a estos manuales

Relacionado con productos y manuales para Equipo Rockwell-automation Logix5000 Controllers I/O and Tag Data Programming