First, thanks you everyone for the great advice. This is a complete, and complex field so I don't expect to be the best at everything at this point in time, or that I ever will be, but I came into this telling myself I'd be the best I could be. Right now, that might not be much, but nothing better to get there than take it one day at a time, and learn from those who walked down the path before you.
I had that (almost) very same issue a few weeks ago. Pump would run fine for 20 minutes then trip the VFD overload. While checking if path was clear, I came upon an analog flowmeter with a small green electrical tape notch, and the flow needle was well over the mark. Being the new guy that I am, I assumed (there we go again with the dirty words) that this meant "above this notch is good, below is bad".
Turns out the drive had been changed, and the parameters weren't put in correctly. Pump was supposed to be limited to 30 Hz, and running at 60 Hz drew sufficient current to trip the overload. 30 Hz caused the flowmeter's needle to point straight to the small green notch.
I had a feeling it was something like that. I greatly enjoy theory, but I feel that in this particular field, it sometimes comes up a bit short. This is a new career for me, but I'm actually 28, and before that, I was a lawyer. In that world, theory is quite a bit closer to reality, so I guess that's where I got this bad habit from.
In this case though, I have to ask : what is the purpose of the different methods we learn if the answer is going to be to do it by feel? What's the use of learning tuning methods if you're going to have to adjust them to imperfect operating conditions? Wouldn't it be simpler just to start with feel?
Thanks!
Honestly, most of the problems I come across are pretty simple and don't really need much in terms of corrective action. Usually, "turning it off and on again" is actually a pretty good guess.
I think one thing has been made clear by the posts in this thread, it's the small stuff that gets you. You can't take anything for granted until you've tested it.
Just in time for Christmas. I love books, so I'm glad there's one on the subject.
The rest of the collection looks pretty tempting too. Do you have them? Care to share your opinion?
With my limited experience, I would tend to agree. I have had a few problems where the machine just wasn't operated correctly. I could have saved a lot of time if I knew how it was supposed to be operated, rather than delving in the program (where every internal bit comes from a huge array of DINTs called...Bits, and with no comments to boot) to figure out where is the thing that doesn't work and how come it doesn't work.
I'm on shift during some of the holidays. If things don't catch on fire, I think I'll take an hour or two and go watch the operators. I don't really want to ask questions, I don't want to bother anybody, but just seeing the machines operated could help me out.
I had that (almost) very same issue a few weeks ago. Pump would run fine for 20 minutes then trip the VFD overload. While checking if path was clear, I came upon an analog flowmeter with a small green electrical tape notch, and the flow needle was well over the mark. Being the new guy that I am, I assumed (there we go again with the dirty words) that this meant "above this notch is good, below is bad".
Turns out the drive had been changed, and the parameters weren't put in correctly. Pump was supposed to be limited to 30 Hz, and running at 60 Hz drew sufficient current to trip the overload. 30 Hz caused the flowmeter's needle to point straight to the small green notch.
I had a feeling it was something like that. I greatly enjoy theory, but I feel that in this particular field, it sometimes comes up a bit short. This is a new career for me, but I'm actually 28, and before that, I was a lawyer. In that world, theory is quite a bit closer to reality, so I guess that's where I got this bad habit from.
In this case though, I have to ask : what is the purpose of the different methods we learn if the answer is going to be to do it by feel? What's the use of learning tuning methods if you're going to have to adjust them to imperfect operating conditions? Wouldn't it be simpler just to start with feel?
Thanks!
Honestly, most of the problems I come across are pretty simple and don't really need much in terms of corrective action. Usually, "turning it off and on again" is actually a pretty good guess.
I think one thing has been made clear by the posts in this thread, it's the small stuff that gets you. You can't take anything for granted until you've tested it.
Just in time for Christmas. I love books, so I'm glad there's one on the subject.
The rest of the collection looks pretty tempting too. Do you have them? Care to share your opinion?
With my limited experience, I would tend to agree. I have had a few problems where the machine just wasn't operated correctly. I could have saved a lot of time if I knew how it was supposed to be operated, rather than delving in the program (where every internal bit comes from a huge array of DINTs called...Bits, and with no comments to boot) to figure out where is the thing that doesn't work and how come it doesn't work.
I'm on shift during some of the holidays. If things don't catch on fire, I think I'll take an hour or two and go watch the operators. I don't really want to ask questions, I don't want to bother anybody, but just seeing the machines operated could help me out.
