DeltaV PID windup current value parameter

[Tim Alosi]

DeltaV PID windup current value parameter

Topic: DeltaV PID windup current value parameter

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Displaying all 3 posts by 2 people.

Post #1

Jim Cahill (Emerson) wroteon February 10, 2009 at 1:52pm

I received an email with this question, "What parameter is available to grab the current value of the windup?"

My search of DeltaV Books Online- http://www.easydeltav.com/bol/10.3
/index.html showed the parameters for windup limits but not for the current value of windup.

Any ideas? Thanks!

Post #2

Qi Yan (China) wrote17 hours ago

We have DV_HI_LIM and DV_LO_LIM.
If you need current value for windup.
You should calculate it.

Post #3

Jim Cahill (Emerson) wrote7 hours ago

I did get some feedback on how this could be done in a calc block. Here it is:

The following is a Calc block expression to set the ARWOP state. Create a module-level named set parameter named ARWOP and a named set windupStates with state names of NONE, HIGH, LOW, and BOTH. PID1 in the expression represents the usage name of the PID block in the module.

if '^/PID1/MODE.ACTUAL' >= 16 then
if ('^/PID1/OUT.ST' & 3)= 0 then
'^/ARWOP.CV' := 'windupStates:NONE';
else
if '^/PID1/OUT.ST' = LIMITED_HIGH then
'^/ARWOP.CV' := 'windupStates:HIGH';
endif;
if '^/PID1/OUT.ST' = LIMITED_LOW then
'^/ARWOP.CV' := 'windupStates:LOW';
endif;
if '^/PID1/OUT.ST' = LIMITED_CONSTANT then
'^/ARWOP.CV' := 'windupStates:BOTH';
endif;
endif;
else
'^/ARWOP.CV' := 'windupStates:NONE';
endif;