I don't recall ever hearing about an Ametek burning up from over amps. Maybe no one else did either, and thats why no responses.
In all the years I been on this board, I never heard of one burning up, ever. Most folks are not likely to post a response unless they know of a situation where it happened, either.
Looks like a case of over thinking the plumbing to me.
And, its not like anyone has the duty to respond to any question here at all.
Bottom line, JW1111, seems to be "Its not an issues that has been reported" at least here.
Anyway. Thats my opinion and probably not held by everyone.
Tom.
"Education consists mainly of what we have unlearned."--Mark Twain[ Parent ]
Not responding is fine but incorrect inferences deflect the focus away from the orignal question. I answered your question. That you don't like the answer is not my problem.
I thought self-protection mechanisms (regulation) were common among production type turbines to prevent them from getting too hot and becommeing damaged. I guess I assumed the ametec motor was not immune to this.
Well, I guess thats the difference between manufactured and required to be idiot proof and Do It Yourself by someone with a clue.
It seems pretty common for folks new to this to over think a lot of stuff that doesn't need to be. Most believe they are thinking "out of the box" but still don't understand the contents of said box.
Personally, I think Ameteks are just toys to get started. Quick and easy with PVC blades but just too many limiting factors to the motor to start with. Adding anything much beyond a prop and a tail is a waste of effort as far as I am concerned.
Might want to look into "Ohms Law", "Watts Law" and some basic electricity information. Because, frankly, this is all pretty basic stuff you should learn about that will help you truly understand why the resistance of the coils will prevent any significant heating from current.
Its your time and resources so feel free to do as you feel necessary.
If you use a large prop for reasonable power the speed issue offers protection. If you use a small fast prop you have less energy capture from the prop and it needs a higher wind to reach the same power out.
Added to this most people using Amtecs are starters, often using pvc or other poorly designed props and this further reduces the risk.
With a good well designed prop and no furling in a high wind it is perfectly possible to burn one out if the bearings hold together long enough. How many amps it will take depends on the duty cycle of the loading ( wind conditions) and time. If you run one on a bench rig you will be limited to something like twice its nominal rating to burn it in a short time. With wind you may have a factor of 3 over this so peaks of 20A may be survived for a fair while before final failure.
Only tiny machines will survive without some form of power limiting and even then I don't feel it justified not to furl or provide some protection.
Yes they are very much starter projects or something to supply small requirements, most people seem to expect too much from them. I really don't see why the sudden interest in such silly things, fine if you accept the limitations and want to start somewhere, but there is a lot of information about suggesting that they will do wonderful things.
These things are ok for a tiny set up in a remote cabin or something but for more serious use you need something much larger unless you are in a very high wind area.
Don't worry about burning it out at 3A or whatever you got.
Flux[ Parent ]
What my comment was about was certain web sites selling what are effectively redundant motors that at one time fetched scrap value and implying that they make 400W wind turbines. You may see a peak near that twice a year but the average daily power is likely to be in the 10's of watts or lower. Your 3A at 18 mph is really quite respectable but I doubt that the average power on most days is anything near your 75W.
If you are stuck with little things then that may be your only option but even a decent 6ft machine would equal the output of 4 of those things at 18mph. Multiple small inefficient and costly machines may be your only option and if it suits you that's fine but for most people one good larger machine would be more cost effective and a more permanent solution.
If the motor comes dirt cheap then fair enough but as to spending more on them than the cost of building a reasonable alternator, that would not be my choice.
Returning to your original question, most use these things at 12v and burn out in a gale is realistically possible but way beyond your 3A. At 24v I doubt that it will ever go fast enough to burn out.
