PID Tuning Software

[Landmine]

A co-worker and I were looking into buying the $200 package together from http://www.pidtuning.net/ but were wondering if we install it on a work computer is it locked to that computer or it is the user it is locked to?

Or maybe there is a better PID Tuning program, maybe a free one? This one does seem worth it, but I wouldnt want to spend $200 of my own money to buy a tool for the company.

[controlgeek]

The FAQ section of the site says:

Can I copy / print out / share my blueprint & tuning software?

All the files are open and unprotected - so yes, feel free to keep multiple copies on different PCs and print out as many copies as you like. All I ask is that you purchase 1 licence for every unique user (or our very reasonably priced site license makes sense if you want more than 4 users). See our very straightforward terms here.

[Landmine]

Well that is awesome! Hopefully I can learn this, prove its value and have the company buy a copy for each of the guys.

[tridiumtech]

Or you can just use the ol' tried-and-true Ziegler-Nichols tuning method. It actually works. You just got to know how to use your CAE tool to figure out the amplitude and period when you get that first oscillation (start out with Gain & Integral at minimum).
But in 17 years of HVAC control, I only had to do the Z-N method once (on a big AHU). Otherwise turning is just parameter based (see attached PDF).

[mechdorn]

A co-worker and I were looking into buying the $200 package together from http://www.pidtuning.net/ but were wondering if we install it on a work computer is it locked to that computer or it is the user it is locked to?

Or maybe there is a better PID Tuning program, maybe a free one? This one does seem worth it, but I wouldnt want to spend $200 of my own money to buy a tool for the company.

Dude, are you that far from tuning your own software? Now, you need another software program to fix your original software PID loops. I think you need to understand the original problem. Loop tuning is usually a pretty easy thing to do. Usually, is a loose term. You can't fix poor engineering with loop tuning. Sometimes you have to track the engineering values when stuff doesn't work the way you would expect.

[orion242]

Ditto.

I wouldn't even think about this snake oil. Every system I have touched treats P, I, D values very differently. No magic software is going to apply to all, even a few I suspect.

PID cannot control piss poor design. You need to learn exactly how the PID calc works, and what the P,I,D terms mean. After dinking around with them enough, you can watch the input variables + output and tune rather quickly. Some systems provide nice charts that update every few seconds to aid, some have specific tuners that work alright at best. Learn the math behind the tuners and you can apply it to your system, assuming you know how your system calculates the PID loop.

Sometimes you need to look at everything in the process, valve type, size, flows, air/water mixing, etc, etc, etc. If a medium pressure steam valve is grossly over sized, your trying to balance a loaded school bus on a needle. Its going to take a wad of programming on top of a normal PID to even get half a$$ control of it. Better off fixing the valve than wasting the time.