Rockwell-automation AADvance Controller Configuration Guide Manuel d'utilisateur télécharger pdf (Page 144)

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ICSTT-RM405f-EN-P

Issue 07

Configuration Guide (AADvance Controller)

 Off will disable the output channel when the module is shutdown due to a loss

of communications with the processor or failure of the module.

 Hold Last State will force the output to remain in its last commanded state

during a module shutdown.

When channels go to Hold Last State other compensating measures

need to be put in place during the failure and the communications must be

restored within the MTTR to maintain the safety rating of the system.

 Default is not used.

5) Select the Disable Line Test and then an option from the two choices of Yes or

No.

 Yes disables reporting of the status variable (STA) state 3. In a no-load

condition the Channel LED will go Amber.

 No enables the line test.



Disabling the Line Test for a Digital Output

The 9451 digital output module checks for a no-load condition on each output. The

AADvance Workbench refers to the check as the 'Line Test'. A no-load condition

occurs when the controller cannot detect a load connected to the field wiring, or the

load current is below 20mA when the output is commanded TRUE.

You can disable the check for a no-load condition, for example if you want to connect

a low load to an output, or if the output is unused and you do not want to fit a dummy

load.

The module reports a no-load condition by setting the state variable (<tagname>.STA)

to the value 3, and by setting the channel LED to amber. If you disable the line test,

then assuming there are no other faults present, the state variable will continue to

show 2 or 4 (depending on the commanded value) instead of 3, and the channel LED

will show off or green instead of amber.

Note: There are other scenarios (such as no field voltage) that still result in an amber

LED, even if you disable the line test.

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Rockwell-automation AADvance Controller Configuration Guide Manuel d'utilisateur Page 144