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  • lindsayb
    replied
    Your Answers

    Well, I can't believe how a simple question about 1 vs 3 phase power turned into such a long thread! I had a lot of fun reading through the whole thing and turns out I did learn some stuff, too. Thanks, everybody, your help and opinions are much appreciated.

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  • Sberry
    replied
    I understand...my point is it seems like many people read so much into duty cycle they get scared away when they will prolly never come close
    One could really get carried away and run on but thats probably closer to reality than not.

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  • FusionKing
    replied
    Originally posted by Fishy Jim View Post
    FK, that duty cycle would kill me. Much of what I do with aluminum is heavy castings with a lot of material to disperse the heat. If I was doing intercoolers, then it might not be an issue. I deal with modifying plenums and there's thick flanges. Part of why I got the invision was to speed up the process with mig.

    I understand...my point is it seems like many people read so much into duty cycle they get scared away when they will prolly never come close. You may in your case.

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  • Fishy Jim
    replied
    FK, that duty cycle would kill me. Much of what I do with aluminum is heavy castings with a lot of material to disperse the heat. If I was doing intercoolers, then it might not be an issue. I deal with modifying plenums and there's thick flanges. Part of why I got the invision was to speed up the process with mig.

    Leave a comment:


  • c wagner
    replied
    Originally posted by FusionKing View Post
    I don't think we disagree at all....in fact I think you have done a much better job at expressing exactly how I feel!!!
    Good deal! Then I guess we agree to ... well ... agree!

    Leave a comment:


  • FusionKing
    replied
    Originally posted by c wagner View Post
    I guess that is where we can agree to see things differently.
    In my eyes and expert fabricator can build anything from start to finish if provided with:
    1) the correct raw materials
    2) the proper tools/ equipment
    3) the skills/ training to operate those tools/ equipment

    I know some people that are awesome welders but they don't read prints very well or can't figure out solutions to problems that often creep up during fabrication.
    I also know some people that simply go above and beyond when it comes time to design/ build things but you don't want them to finish weld it or... well lets just say it takes away from the beauty of the rest of the project.

    Here is what dictionary.com has to say on the subject:

    4 dictionary results for: fabricator
    Dictionary.com Unabridged (v 1.1) - Cite This Source - Share This
    fab·ri·cate /ˈfæbrɪˌkeɪt/ Pronunciation Key - Show Spelled Pronunciation[fab-ri-keyt] Pronunciation Key - Show IPA Pronunciation
    –verb (used with object), -cat·ed, -cat·ing.
    1. to make by art or skill and labor; construct: The finest craftspeople fabricated this clock.
    2. to make by assembling parts or sections.
    3. to devise or invent (a legend, lie, etc.).
    4. to fake; forge (a document, signature, etc.).
    [Origin: 1400–50; late ME < L fabricātus made, ptp. of fabricāre.
    I don't think we disagree at all....in fact I think you have done a much better job at expressing exactly how I feel!!!

    Leave a comment:


  • FusionKing
    replied
    I'm not sure that the older Dynasty 200 showed any difference on three phase either. I believe it was simply misread frequently... IIRC.

    In fact I just read my older manual and it says they are the same duty cycle wise between single and 3 phase.
    It is easily misread because they rate 115v as well. Page 13 is a pretty good chart IMO.
    But the chart on page 15 does make it seem that better welding with more power would be possible at max amperage.

    Jim I would like to say if you would use a Dynasty 200 for a length of time you would certainly want one for yourself and much of this discussion would be agreeing with each other. It isn't like a little MiG machine with a low duty cycle at all. The fact that you vary your amps when welding weighs heavily into this. As for stick it will run 1/8" 7018's nonstop forever.

    Leave a comment:


  • Fishy Jim
    replied
    Like I said, I wasn't aware that they had bridged this gap. I was clearly wrong because the units I had been shopping (recently) when looking into buying my invision also have the output hit.

    I still consider duty cycle just as important as the stated output figure though. Output amperage has to lie within an acceptable cycle time or the rated output isn't accurate in determining the machines ability to accomplish the task.

    Leave a comment:


  • MAC702
    replied
    Originally posted by Fishy Jim
    The inverters max power is greatly reduced on single phase.
    Originally posted by KB Fabrications View Post
    This is at best misleading and in reality, completely untrue. For instance, the maximum output of my Dynasty 350DX is 350 amps whether it be single or three-phase power. ...
    Jim, if your next post after this exchange had been like this:

    Oops, you're right Kevin. I meant to say that many machines would show significantly less output over time, or even have what I would think to be an unusably low duty cycle, that it should be taken into account.
    There would never have been a page 9 to this thread. You are used to arguing and quick to assume we WANT to argue with you. Just clarify what you meant and accept that your initial wording was wrong and misleading. Or just jump down the throat of anyone who tries to clarify it for you. Your choice.

    Leave a comment:


  • Fishy Jim
    replied
    Originally posted by MAC702 View Post
    Duty cycles aside, the max outputs ARE THE SAME on these machines (Dynasties and some others, no doubt.) End of story. Did you check the volt-amp curves? I'm not mistaking amperage for power. It's in the graph, and it's not nearly as complicated as a sine wave. And it's past the section on "rated outputs" which is for marketing.

    20% is a far cry from saying it is an unusable output. The power is there and usable!

    Again, if you say "max output over time" you'd be correct. But that is not nit-picking, that is an extremely important detail that changes the whole game.

    Mac, I know the stated outputs are the same, but the practical implication of these differences is over time (you know, while working). I'm not confused by sine waves, there again, you and I have a very different opinion as to which is an important vs superficial aspect of the problem. I contend that duty cycle at a given output is as critical as the actual output rating in amperage.

    If I'm welding something that needs the max output of the machine, I have a strong feeling (it is my belief, you can disagree with it) that duty cycle will become a very vital issue in the effectiveness of said machine to accomplish the task. 20% would not be a moot point in such a situation, as it has been in my personal experience with at least two machines with said 20% duty cycles.

    If in fact the new dynasty's have no difference in duty cycle between the two input phase options, then there would be no way to discern which was being utilized as the arc characteristics should be identical due to the effective filtering of the switching power supply.

    Leave a comment:


  • c wagner
    replied
    Originally posted by FusionKing View Post
    But for further clarification I would not call an "expert" press brake guru a fabricator, nor do I feel a fabricator needs to be an expert press brake operator to be an "expert" fabricator
    I guess that is where we can agree to see things differently.
    In my eyes and expert fabricator can build anything from start to finish if provided with:
    1) the correct raw materials
    2) the proper tools/ equipment
    3) the skills/ training to operate those tools/ equipment

    I know some people that are awesome welders but they don't read prints very well or can't figure out solutions to problems that often creep up during fabrication.
    I also know some people that simply go above and beyond when it comes time to design/ build things but you don't want them to finish weld it or... well lets just say it takes away from the beauty of the rest of the project.

    Here is what dictionary.com has to say on the subject:

    4 dictionary results for: fabricator
    Dictionary.com Unabridged (v 1.1) - Cite This Source - Share This
    fab·ri·cate /ˈfæbrɪˌkeɪt/ Pronunciation Key - Show Spelled Pronunciation[fab-ri-keyt] Pronunciation Key - Show IPA Pronunciation
    –verb (used with object), -cat·ed, -cat·ing.
    1. to make by art or skill and labor; construct: The finest craftspeople fabricated this clock.
    2. to make by assembling parts or sections.
    3. to devise or invent (a legend, lie, etc.).
    4. to fake; forge (a document, signature, etc.).
    [Origin: 1400–50; late ME < L fabricātus made, ptp. of fabricāre.

    Leave a comment:


  • MAC702
    replied
    Duty cycles aside, the max outputs ARE THE SAME on these machines (Dynasties and some others, no doubt.) End of story. Did you check the volt-amp curves? I'm not mistaking amperage for power. It's in the graph, and it's not nearly as complicated as a sine wave. And it's past the section on "rated outputs" which is for marketing.

    20% is a far cry from saying it is an unusable output. The power is there and usable!

    Again, if you say "max output over time" you'd be correct. But that is not nit-picking, that is an extremely important detail that changes the whole game.

    Something pithy is condensed and terse, but has all the substance needed. Leaving out critical details does not make one pithy. It makes them wrong.
    Last edited by MAC702; 10-17-2008, 12:21 AM.

    Leave a comment:


  • Fishy Jim
    replied
    The max output would encounter a duty cycle fault on single phase in most cases when attempting to melt the most metal. I see everything since as nit picking. You perceive my "most metal" as an acute thickness issue, not volume. Perhaps I was too vague given the scrutiny of this audience. I'll try not to be pithy in the future.

    Leave a comment:


  • MAC702
    replied
    Jim, if you took the word "max" out of your first statement in that post, I don't think I'd have a problem with what you said. I completely agree that the machine is less efficient.

    I also will side with you that IN MANY MACHINES, like my PowCon 300SM, you WILL have less maximum output on single-phase than three-phase. But then again, in single-phase, it operates only from 230V and on three-phase, it operates only from 460V. But that's just my machine.

    I feel your initial statement was too broad to be accurate and there was no malice in trying to point that out to you.

    Also, you quoted "rated outputs" when we were clearly talking about maximum outputs. That was black and white, and you tried to steer us through it without admitting you used the wrong data.

    Leave a comment:


  • Fishy Jim
    replied
    Mac, here's my original post on the subject - unedited.

    Originally posted by Fishy Jim View Post
    The inverters max power is greatly reduced on single phase. Without ever looking at the machine, I think you could get a really good idea which input power was being used by simply turning up the heat as high as it goes and seeing which melted more metal. Same machine, same operator, same input voltage = vastly different output based on input being single or three phase.

    Now if you were intending to limit the test parameters to a given welding current within the range of both phase types, then I would agree with you.

    I don't have any 3ph tig experience, but my inverter mig supply is every bit as silky as the 3ph transformer migs I've run.
    What I said was that you could tell without looking at the input power, with somewhat certainty, what the machine was running on based on it's ability to melt a volume of metal. You, and others, perceived this as saying that the sole distinction of max power is amperage which I disagree with. Sure, I responded with the duty cycle based information, because I think to compare a machine based on anything but amperage and cycle time combined as a single parameter is foolish and misleading in it's own right (like the air compressor motors). While I didn't know that they eliminated the difference in the new dynasty (which has been on the market for what, 6 weeks now?), the case remains the same in much of the inverters out there (we could hope they'd change that, it would make a dyn 350 a lot more attractive to me).

    Leave a comment:

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