Rockwell Automation T8031 Trusted Valve Manager - Manual (Page 23)

Trusted
TM
Valve Manager T8031
Issue 2 Oct 05 PD-T8031 23
Test Error (it sets VTM to 3), then the Valve Manager will reset the VTEST function block by setting
VTS to FALSE. This allows the VTEST function block to monitor for any subsequent changes to the
valve’s Digital Output.
It is anticipated that certain applications will require direct control of the End State and/or End Time
values for a given valve. Access to either variable can be removed without impact to the Valve
Manager, though removing access to both will prevent the automated collection of transition times from
operating correctly and will generate unnecessary and/or unwanted valve tests when the Valve
Manager attempts to reset the function block. Access to either variable can be accomplished in
several ways, but the recommended approach is to not connect the “_EST” or “_ETM” variables to
their respective “_ESO” or “_ETO” outputs. If access to either variable is removed, it becomes the
application’s responsibility to ensure that an appropriate value is presented to the module for a valve
test, as the Valve Manager will no longer be able to automatically use value configured in the valve’s
profile.
2.3.3. Automated Testing using Valve Test Start (VTS)
While the Valve Manager is capable of manually initiating a valve test, it is possible to automatically
initiate tests through application logic. In such cases, the Valve Manager will still collect the test
results. Automated valve testing is configured by having the application set VTS to TRUE to initiate a
test, but allowing the Valve Manager to set VTS to FALSE after the data has been collected.
The following is an example of how to accomplish automated testing through application. In the
example, a rising edge of the variable “test_trigger” will initiate a valve test.
Figure 18 Automated Testing Logic