seth Posted March 15 Share Posted March 15 Hi, Is there a way to read or write the integral value in a DAQFactory PID loop? I am looking to reduce large jumps when initializing a PID loop in-situ by setting the I term before beginning the loop but I do not see a way to do that currently. Thanks! Quote Link to comment Share on other sites More sharing options...
AzeoTech Posted March 16 Share Posted March 16 You can use the PID's event to manage the loop. See section 10.4 for more detail. You can't change the actual accumulated I parameter from script. You could, however, set the IntLimit parameter to, say, 1e-9 for an iteration or two after starting and that should essentially reset the accumulated I. Also note that Reset on SP change will cause the accumulated I to reset whenever the SP changes. You can just tweak the SP by a very small amount and it will reset the accumulated I. Of course Reset on Start will do this as well whenever you start the PID loop. Quote Link to comment Share on other sites More sharing options...
seth Posted March 17 Author Share Posted March 17 I am looking to do the opposite of reset on start, I want to pre-load a value into the integral before starting the PID loop for a smooth transition. I guess specifically what I am looking for is "bumpless transfer", pre-loading the integral value is one way to accomplish this. If there are other ways to accomplish this in DAQFactory please let me know! Thanks! Quote Link to comment Share on other sites More sharing options...
AzeoTech Posted March 17 Share Posted March 17 We will look to add that in the next release (20.2). It should be quite easy for us to do. Quote Link to comment Share on other sites More sharing options...
seth Posted March 18 Author Share Posted March 18 Cool, thanks! Is there an expected release date for 20.2? Just wondering if I should look for a workaround for the near future or if it will be released soon Quote Link to comment Share on other sites More sharing options...
AzeoTech Posted March 19 Share Posted March 19 Now that we finally have 20.1 out I expect we will do rapid releases, maybe once a month. The next one should be within a week. It will likely be numbered 20.11 and it will include access to the PID integral sum under the variable "IntSum". It is read/write. Quote Link to comment Share on other sites More sharing options...
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