welders welders welders

[blue9249]

ok guys just wanted to let you know i am having internet problems (server reset error codes every 5 minutes) was kinda surprised when i logged in quick to post this that the thread is at 6 pages, i just want to let you guys know that i am here and when i get this internet issued resolved i will have some time to answer some questions. i figure it will be a little while to fix this issue as it only triggers on some sites and is intermittent so i am having a hard time back logging to try and find the source of the problem

 

[sd455dan]

Jim, the Maxtron will run on single OR 3 phase. (100% duty cycle @450 amps on 3 phase. )

View attachment 456437

Terry

-
Wow the Maxtrons have some impressive power and duty cycle ratings,- Jim got a great deal on that model machine.
From what i gather the Maxtron is an early generation inverter?

This brings up something that seems to be inherently different between transformer and inverter welders

Duty cycles of many of the new inverter welders including my inexpensive chinese made Lotos appear to be rated at 60% and also 100% dc.

But most new (consumer/homeowner) transformer based welders are generally rated at less than half those duty cycles.


Thoughts?


I do think inverters are the future of welders, but do like the old transformer machines imo they are much less complicated to fix when something does go wrong and that isn't often. :stirthepot:

 

[Shield Arc]

I do think inverters are the future of welders, but do like the old transformer machines imo they are much less complicated to fix when something does go wrong and that isn't often. :stirthepot:

Does make you wonder how long these inverter welders will last.
I have a 1937 Lincoln that is still going strong.:thumbsup:

 

[Sodo]

They only have to last long enough to satisfy the customer. And they may well do that because customers can afford bigger machines than they need, never stressing it.

It could be just "rating number inflation". When customers become focused on a number that nobody has a real need for, it becomes a race. Marketers start to escalate that number, each year it gets bigger. Like lawnmower horsepower, they used to be 3.5HP, and then went to 4. WOW. Now they're all 6.5 hp. Really? What changed? Is this 6.5HP a "governed HP" or "overspeed HP"? Who's checking? Last year they bumped the number and sold more mowers, now all mfrs have to pony up and bump their numbers too.

A chinese mfr (or American marketer) can claim 60% because their buyer will never outweld 20% anyway. Nobody really NEEDS to outweld 20% (except for sport) so customers will never know. Only an aggressive production shop could know such things and they don't buy discount machines, nor care.

All these "excesses" must happen on a job, and they don't match a consumer workflow.

- The job requires machine set at MAX output
- All cutting and fitting was done in advance (it's just weld, weld, weld, for hours, nothing else).
- Timeline doesn't allow stop-time, re-position for next weld as fast as possible.
- Weldor is "physically capable" of weld weld weld
- Someone is cracking the whip

If the above conditions are often, additional money spent for duty cycle may be recouped.

IMHO, YMMV. Here's my entire duty cycle knowledge (re-re-re-stated). Never in 25 years have my Miller or Hobart MIGs shut down.
My Miller is rated 20% (=2 minutes welding in 10, then cooldown) and I welded 25 minutes straight once as a test. MultiMatic200 is rated for 3/8" steel and was welding 3/16" (wasn't running at MAX) did not shut down period. I suspect it's around 40% (4 minutes welding in 10, then cooldown) at that setting.

Dan you asked for "thoughts".:thumbsup:

My thoughts are that bigger Duty-cycle numbers produce higher profits, same as HP on mowers.

 

[Big Barn]

Shield Arc: Your welder's baby brother came along a little later, but still hummin'....



NB. Overspray on wheels have since been removed.

Terry

 

[Jim Timber]

My thoughts are that bigger Duty-cycle numbers produce higher profits, same as HP on mowers.

I hit the thermal limit on my MM130XP more than once too. But back then I was a noobie hack.

 

[Sodo]

Good thing those days are gone huh? There could be benefits to being a noobie again though.

 

[Jim Timber]

There could be benefits to being a noobie again though.

Like what?

 

[Sodo]

Ask Terry :laughing:

 

[flyerdan]

It's just a guess, but I would speculate that the inverter machines might have a higher duty cycle because the transformer machines have far more mass, and it takes longer to cool down. Just like a cast iron skillet will hold heat longer than an aluminum pie pan.

 

[Jim Timber]

Except that on the cheaper welders (like Hobart vs Miller) they use aluminum windings in the transformer and those are the lower duty cycle machines. Copper probably retains heat better than aluminum.

Do inverters still use transformers to lower the output voltage down from the line voltage, or do they chop it to make an average?

 

[Sodo]

Makes sense. By the time a transformer machine is warmed up there's a lot of heat stored in that mass. Some of these old weldors can take a while to cool down. Inverter machine turns the fan on as soon as it starts to warm up. If the fan can keep up, it's no problem. And it cools down quick too. I suspect the whole duty-cycle thing is based on old eqpt from years ago and will be with us for awhile. Longer if the noobs adopt it and keep it alive.

That's one thing I've learned about tradition, people under 30 don't care for tradition they wanna make their own world. It's the old farts who care about tradition.

I don't know how an inverter does it. Inverters have some "capacity" in them. Mine has to run the fan to purge that storage everytime I shut it off.

 

[sd455dan]

Except that on the cheaper welders (like Hobart vs Miller) they use aluminum windings in the transformer and those are the lower duty cycle machines. Copper probably retains heat better than aluminum.

Do inverters still use transformers to lower the output voltage down from the line voltage, or do they chop it to make an average?

From what i have read they still use transformers ( at least 2 -although Much smaller and lighter) due to the much higher frequencies they switch at.

Interesting to me- doing a little research (looking for replacement transistors should my new offshore welder / plasma cutter go BOOM).:laughing:

Was a pre production inverter welder that Siemens (Infineon) built to market their new Trench Stop 5 IGBT modules and individual transistors.
if interested here is a pdf about the tech http://www.infineon.com/dgdl/Infine...n.pdf?fileId=5546d46147a9c2e40147ce6f0a197daf

Looks like we may soon see 100 KHz + full bridge inverter welders rated @ 250 amps with just 4 IGBT output transistors in a smaller, simpler and 35% lighter package possibly under 20 lbs. with more reliability and more affordable than the current off shore inverters.

 

[C4Ranch]

C4Ranch I hope I'm not pi**ing you off I enjoy your posts - I'm just having some fun, but seems like duty-cycle needs discussion.

Not at all. I appreciate the conversation and am here to learn. I like real world tests, that's what really matters. I live in marketing so I understand and numbers are just another thing to look at wether it's relevant or not. IIRC my Lincoln 210mp is 25% at 200 amps. Does that mean it's working less than a 20% machinery? I donno.... The owners manual calls out that it will shut down and flash an icon if it is overworked. Hope that means it will protect it's self if I do go wild and weld non stop at high Amps for a long time. But you're absolutely right. I have yet to hit it and most of my welding is short spurts, repair, etc.

 

[Silvic]

It always intrigues me that the folks that know the most tend to have a level of self-deprecation while letting people know they have the knowledge to back up their statements.
On the flip side the folks that know the least tend to try to build themselves up and beat their chests in self-importance while trying to belittle others.
Why is that?

 

[MinnesotaDaveChalmers]

It always intrigues me that the folks that know the most tend to have a level of self-deprecation while letting people know they have the knowledge to back up their statements.
On the flip side the folks that know the least tend to try to build themselves up and beat their chests in self-importance while trying to belittle others.
Why is that?

I often think those type of questions boil down to the "Dunning-Kruger effect."
It is an interesting bit of reading that reminds me to evaluate where I fall on that scale.

 

[Silvic]

I often think those type of questions boil down to the "Dunning-Kruger effect."
It is an interesting bit of reading that reminds me to evaluate where I fall on that scale.

Wow the things I learn on TBN. Thanks I had not heard of the study. Did a bit of google search and came up with the sentence of the day for me.

"Unfortunately the problem with the Dunning-Kruger effect is that incompetent people have probably been getting this type of feedback for years and failed to take much notice.
Despite failing exams, messing up at work and irritating other people, the incompetent still don’t believe they’re incompetent."


I knew I liked reading your posts.

 

[Sodo]

Some people enjoy discussion, others want to tell you how it is, don't want discussion. If you're learning from the latter, better be sure what you're learning - is what you NEED.

Dave I like your sig line.

Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~

 

[k0ua]

Here is what I know (which ain't much) I fed 5 7018 rods at 125 amps thru my tiny little PA160 Everlast machine Just as fast as I could clip a new rod into the stinger. That is the most rod I have burned back to back at one time. No only did the little inverter welder which is rated for a 60% duty cycle go into overtemp, but it wasn't even warm when I touched its case. It's little fan runs all the time. I needed a break, but the little thing was begging for more rod. How that plays into this discussion I will let you all decide.

 

[Shield Arc]

It always intrigues me that the folks that know the most tend to have a level of self-deprecation while letting people know they have the knowledge to back up their statements.
On the flip side the folks that know the least tend to try to build themselves up and beat their chests in self-importance while trying to belittle others.
Why is that?

Silvic I think that is just the nature of some people. I live in a county with three Navy ship yards. The workers in these ship yards are convinced they are the only ones on the planet that can do anything. In the mid 1980s I was working on a 135-feet x 135-feet x 60-feet deep cofferdam inside Puget Sound Navy Shipyard. The cofferdam was all sheet piles driven to grade. Then a tieback, and whaler system every 10-feet in height. The tiebacks were tensioned with a 100-ton jack. The whaler system had five welders running wire feeders. We had a very hard time getting enough qualified help out of the union hall. Few months after completing the cofferdam I ran into a guy who worked as a rigger in the ship yard. He informed me they were going to build this cofferdam in house, but decided to let construction workers have the work.
Makes me wonder how many years it would have taken these ship yard workers to build this cofferdam.