AC SMAW on an inverter power source question

[cruizer]

Yes, the fellas running a weld from a basic Transformer from other countries is just that, they are not using an actual welder, instead they are using a stepdown non regulated and non grounded transformer pulled out of a scrap heap, which generally is directly tied into another unregulated power off a supply line. No breakers or saftey to speak of.

I on the other hand was talking about an actual regulated brand of AC welding machine which it would be tough to kill yourself with.

[cws612]

I beg your pardon? I ran a 3 wire subarc for the better part of a year in a large vessel shop. One head was DCSP, one head was DCRP and one head was AC and all running 5/32 or 3/16, so yah, don't worry, I've heard of it. I can see that you are kind of the king pin around here but I'm no newbie to welding. Maybe a newbie to this board but that's it. As far as the dangers of AC welding welding goes, just ask the older Czech, Serbian and Polish welders that come over here from the old country about it. They will tell you stories. Either way, that's all beside the point with regard to this discussion and the OP's question.

yea, he's pretty much a kingpin around here. he's earned the respect he gets by freely offering knowledgable info, aid, and insight to anyone who requests it. (even subarc experts with a whole year of working in a pressure vessel shop). if you lurk here a while you will observe that there is a core group of real experts of which cruizir is one, that make this forum the info source that it is.

[Matrix]

Excuse me? Did I say "kill"? No, I said "electrocute". You know there's a difference, right? People are electrocuted every day without dying. Lots of people. Shoot, people get struck by lightning and live to tell the story.

And why are we arguing about this, exactly? How is this relevant to the original question?

This is now the second time in a week that someone has taken my comment out of context and then also tried to put words in my mouth just to create some kind of an argument. You have a funny way of welcoming new members around here. So, I'm new. So what. Does that mean you have to try to keep me on the defensive every second? Over a non-issue like AC stick welding that you hardly ever see anymore and that somehow morphs into an argument about submerged arc welding? What's that all about?

[go2building]

WOW!! One thing I do know, my Miller Bobcat has a caution symbol next to the A/C welding process selection. When Tesla invented A/C power he was criticized and told his A/C power was far more dangerous than the DC power being used at the time.
Just my .02 on this ****
Kevin

[Matrix]

WOW!! One thing I do know, my Miller Bobcat has a caution symbol next to the A/C welding process selection. When Tesla invented A/C power he was criticized and told his A/C power was far more dangerous than the DC power being used at the time.
Just my .02 on this ****
Kevin

Exactly. Out of curiosity I decided to take a peek in the owners manual on my Dynasty 200DX, which just happens to be the exact topic of discussion in this thread if anyone cares to remember.

On the very first page in section 1-2 under the heading "Arc Welding Hazards" are warnings on of the dangers of selecting AC output welding current.

And I quote:

- Wear dry, hole free insulating gloves and body protection
- Insulate yourself from work and ground using dry insulating mats big enough to prevent physical contact with the work or ground.
- Do not use AC output in damp areas, if movement is confined or if there is a danger of falling.
- Use AC output ONLY if required by the process.

(In large bold letters)
ELECTRIC SHOCK can kill.
With symbols depicting a weldor touching the end of the electrode and electric current running through the man's body.

Sure sounds to me like Miller thinks maybe there are a few safety concerns with AC welding. They tell you to take measures to prevent contact with the work or the ground and they show you a picture of a man touching the electrode and being electrocuted but never mind any of that, Cruiser knows best and it doesn't matter anyway because we take a crap all over the new people here whether they are right or wrong.

[Helios]

Excuse me? Did I say "kill"? No, I said "electrocute". You know there's a difference, right? People are electrocuted every day without dying. Lots of people.

Really?

electrocute

1. to execute (a criminal) by electricity

2. to kill by electric shock

Looks to me like everyone who's ever been electrocuted is deader than a doornail.

[GilaSlim]

If you die, you have been electrocuted. If you don't die, you have been shocked. Helios' definition is correct. I have been shocked more than once, but fortunately never electroctued.

Yes, AC is more dangerous than DC. At 60 Hz, AC frequency is similar to the frequency of the electric pulses that control the heart, and can interfere with it. Edison, in his fight against AC would electrocute (kill) elephants in public spectacles to prove his point. Over 130 years of experience has proven that AC can be used safely, if handled properly. Miller's warnings are appropriate, and necessary for those lacking experience with AC.

Matrix, nobody is "taking a crap" on you just because you are new. The problem is you display an argumentative attitude, you are always right, and you get whiny when anyone disagrees with you.

Cruizer is a recognized, well respected expert on this board. We are lucky to have him here. Yes, he can sometimes be abrupt in his responses, but he does not "take a crap" on new guys.

Suck it up, dude. Don't be so sensitive. Recognize that people will sometimes disagree with you.

[Matrix]

When someone takes your comment out of context and then tries to make it look like you said something you did not say so that they can create an argument ... that is not disgreeing with an opinion. That is called picking a fight. Don't think for a second that I don't know the difference.

My apology for my misuse of the word electrocute.

That apology does not change the fact that AC welding is more dangerous than DC welding and it also does not change the fact that there never should have been a debate on it in the first place because only a fool would argue that AC welding is as safe as DC welding, especially when you steer the conversation away from the original context. (SMAW vs SAW) Except for my unfortunate misuse of the word electrocute there was nothing in my comment that anyone should have taken exception to enough to start an argument over.

As for my being argumentative, well I see it another way. I see how two people in the last week have been argumentative with me first. I didn't start either fight. You can call that a difference of opinion if you like. I prefer to call it what it is.

[Arizona Joe]

...AC welding is more dangerous than DC welding...

Matrix, after thinking about this, I believe you are correct! (The emphases are mine.) This is specific to welding. However, in general, I do not believe that AC is more dangerous than DC. And as for Edison's demonstration, it was pure rubbish. DC would've worked just as well.
http://en.wikipedia.org/wiki/Topsy_(elephant)
"Topsy was fed carrots laced with 460 grams of potassium cyanide before the deadly current from a 6,600-volt AC source was sent coursing through her body, partly as a demonstration of how "unsafe" his competitor's (Nikola Tesla) alternating current design was."

Now, getting back to welding, there is a stinger and a work clamp, sometimes, erroneously called a ground clamp. One is the source, and the other is the return. Every circuit needs a source and a return. A ground is a source of zero potential. It is not necessarily a return, although it can be.

In DCEP, the stinger is the source and the work clamp is the return which is at zero potential. If you are standing barefoot in a steel bucket of salt water resting on a steel floor and grab the stinger you will probably get a shock. If, on the other hand you grab the work clamp you will not a get a shock.

Now, on an AC welder, like a transformer buzz box, the roles of the stinger and work clamp change from source to return and return and source 60 times a second. So, the work clamp as well as the stinger are both hot all the time. Now when you stand in the water you will probably get a shock if you touch either the stinger or the work clamp.

I've been a welder for two whole months now While far from being an expert still, this is the way I think it works. So, guys and gals, have at it. I'm here to learn.

[paulrbrown]

Well Weldors: I do not have the numbers in front of me, but in the past, I read somewhere that it takes one heck of a lot less AC to stop your heart as it does DC. I will try and find, but I am thinking it is 1/100 or 1/1000 less.....bear with me while I research......hope this helps.....and yes, I have tried welding SMAW with AC on my 200DX, I have even pulse welded SMAW with my SynchroWave 250, but that was DCEP.....kinda kool too.....hope this helps.....Matrix, you will find some smarty pants folks here, but most are quite Humble, I joined in 03, even though it does not show it....a format change ended up giving me a later join date....Cruizer is a good guy....and yes, sometimes abrupt.....but still a good guy, Welcome to the Forum.....Hope this Helps, and I am researching that voltage info now....Paul