David M. Posted July 5, 2009 Report Share Posted July 5, 2009 Hai all, I make a VI from the example of water tank level... I want to make the water tank have a PID control... but the VI don't run as I wish... may be you can help me to tell me where is the error... thanks... uji coba.vi Quote Link to comment
Bug Posted July 15, 2009 Report Share Posted July 15, 2009 Hai all, I make a VI from the example of water tank level... I want to make the water tank have a PID control... but the VI don't run as I wish... may be you can help me to tell me where is the error... thanks... Dear David, You have not posted the complete project. The VI is not getting downloaded completely. And does not open in LV Regards, Bug Quote Link to comment
David M. Posted July 19, 2009 Author Report Share Posted July 19, 2009 Dear David, You have not posted the complete project. The VI is not getting downloaded completely. And does not open in LV Regards, Bug Here is the new VI and sub VI thnx Jadi.vi Qin.vi Qout.vi PID.vi limitter.vi Quote Link to comment
Kurt Friday Posted July 19, 2009 Report Share Posted July 19, 2009 (edited) One vi is missing "Level.vi Also, can you be a bit more explicit in describing the problems that you are having with your solution. What tests have you done on your code that are showing the issue? Present as much information as you can that demonstrates that you have had a good go at trying to resolve the issue. Edited July 19, 2009 by SciWare Quote Link to comment
David M. Posted July 23, 2009 Author Report Share Posted July 23, 2009 One vi is missing "Level.vi Also, can you be a bit more explicit in describing the problems that you are having with your solution. What tests have you done on your code that are showing the issue? Present as much information as you can that demonstrates that you have had a good go at trying to resolve the issue. the level VI is already in the example... I make that simulation from an example in the "Industry aplication" then "Process control"... the name is "Tank Simulation.vi" I have modify the VI, include the limitter of the "on-off" control... so the simulation will only fill the tank until some state and then control the in put water until the input equal with the out put... I'm a litle confuse how to tell you about this simulation because I study this program with "trial and error" not with a book... sorry if my english doesn't good enough... thanks before... Quote Link to comment
Kurt Friday Posted July 24, 2009 Report Share Posted July 24, 2009 the level VI is already in the example...I make that simulation from an example in the "Industry aplication" then "Process control"...the name is "Tank Simulation.vi"I have modify the VI, include the limitter of the "on-off" control...so the simulation will only fill the tank until some state and then control the in put water until the input equal with the out put...I'm a litle confuse how to tell you about this simulation because I study this program with "trial and error" not with a book...sorry if my english doesn't good enough...thanks before... Hey David Ok, I didn't realize it was built from an example, so I've got it now. You are almost there, I'm able to get it working however there are a few issues that I was able to identify and may have contributed to it not functioning as expected. 1) Initialize your shift registers and feedback nodes. 2) Your PID isn't tuned properly try setting Inflow Rate = 1000 L/sec, Off Limit = 20 cm, High Level Limit (setpoint) = 10cm PID Limit = 5 I was able to get PID control of the tank, but its oscillating quite badly so experiment with the settings till you get it right. Some suggestions to make your code better. 1) You have subvi's with uninitialized shift registers, have an initialize Boolean that initializes the shift registers with appropriate default values. 2) Your subvi's are a little confusing as you are not following the connector pane convention of inputs on the left outputs on the right, if you are running out of terminals to follow the convention then try a connector pane pattern with more terminals or try using a cluster, ie your PID inputs could be input as a cluster. Hope this helps Quote Link to comment
David M. Posted July 25, 2009 Author Report Share Posted July 25, 2009 Thanks for your help, I'll try to initialize the feed back nodes and the shift register... but about the connector pane, may be I can't make a cluster to fix it... because I realy confuse when I make VI with cluster... Sorry, I'm a new user for Lab VIEW program... I just study it for about 1 year (from last year)... May be I really need help for study it... I'll try to make my VI better and then I'll post it here, so you can help me to check the VI again... sorry to bother you... thanks a lot... Quote Link to comment
Kurt Friday Posted July 26, 2009 Report Share Posted July 26, 2009 sorry to bother you... thanks a lot... No problem, happy to help Quote Link to comment
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