The Museum of HP Calculators

HP Forum Archive 04

 PID Program Listing Message #1 Posted by Hugo (Quebec,Canada) on 13 Dec 2000, 9:47 a.m. I'm interested in any program listing concerning PID stuff. It can be for HP-41C/42S, 71B, 75C, 67, 48xx, 32SII, 28S, 25 I don't care since I have all of them as long as it related to PID. Thanks. Hugo

 Re: PID Program Listing Message #2 Posted by Fred (France) on 13 Dec 2000, 9:53 a.m.,in response to message #1 by Hugo (Quebec,Canada) I'm sorry but : what is PID ????

 Re: PID Program Listing Message #3 Posted by Yos Feit(NY, NY) on 14 Dec 2000, 9:18 a.m.,in response to message #2 by Fred (France) PID = proportional, integral, differential This describes the classic equation for feedback loop control, normally used in industrial process control. For example, a heating system (like a house) would have temperature as the stimulus and heat energy as the response. The controller calculates the PID equation using temperature as the variable and the result is the amount of heat to produce at the moment. When started, the heater will output at 100%, and as the temperature approaches the set point it will then cut back to some small constant output level. The chosen computer must calculate the equation in a loop fast enough to keep up with the changes in the stimulus. Thus an HP 41 is probably fine for home heating but not for anti lock brakes or a rocket engine.

 Re: PID Program Listing Message #4 Posted by Hugo (Quebec,Canada) on 14 Dec 2000, 9:36 a.m.,in response to message #2 by Fred (France) It's related to industrial automation process. If you want to learn more about this let me know. Hugoo

 Re: PID Program Listing Message #5 Posted by Ron Ross on 14 Dec 2000, 9:27 p.m.,in response to message #4 by Hugo (Quebec,Canada) You will find a program to compute PID, PI and Pb parameters for the HP67/97 caclulator in a book called "Practical Process Instrumentationa & Control" Volume II. The article is on page 58 and is titled "Calculator program for new controller-tuning method" and takes 224 steps on an HP67. This means it should run on the following "modern HP's", the HP11 (tight fit), Hp15, Hp32s??, Hp42s, HP41 (almost forgot). with minimal changes. If you list a fax, I may photocopy and fax program listing sometime in next week. Regards,

 Re: PID Program Listing Message #6 Posted by Hugo (Quebec,Canada) on 14 Dec 2000, 10:03 p.m.,in response to message #5 by Ron Ross I would REALLY apppriciate if you can do that for me. Email-me privatly, I'll give you my fax number. Thanks Hugo

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