3/18/2016 7:48 AM | |
Joined: 3/14/2008 Last visit: 8/16/2024 Posts: 2086 Rating:
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Hi Autoguy, Please take a look at the APL v8.1 library template-> "OverrideControl". It is based on two PIDConL controllers which share a common actuator. You may adjust it to you needs. Just quick thinking: You also can use the "ER" output of the PIDConL to determine the amount of difference between PV en SP. Then you can compare this with a parameter and activate the PIDConL (MV_TrkOn=0) and interlock the second PIDConL. |
If I could help you, you can use the RATE button. Thank you. |
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3/18/2016 12:27 PM | |
Joined: 3/14/2008 Last visit: 8/16/2024 Posts: 2086 Rating:
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You have to set variable "NegGain" for the controller with negative gain. The error by the way (ER) is calculated as follows: SP - PV_Out. |
If I could help you, you can use the RATE button. Thank you. |
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3/18/2016 1:28 PM | |
Joined: 3/14/2008 Last visit: 8/16/2024 Posts: 2086 Rating:
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Well, you have to arrange the system in such a way, that taking over by the controllers is smoothly. I have a good document with an example, also override control, which has a flow and pressure controller, where the pressure controller has a negative gain: Flow controller-> Positive gain because when valve opens, flow increases, Pressure controller-> Negative gain because when opening the valve, the pressure drops. So I suggest you read the document, I think it's much clearer to you if you have the pictures and explanations rather then me talking here Attachment44229396_overridectrl_en.pdf (315 Downloads) |
If I could help you, you can use the RATE button. Thank you. |
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