Welding amps vs breaker size amps.

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Could someone take the time to explain in laymans terms how a mig welder or stick welder with a 50 amp breaker is capeable of a setting more than that breakers rating? For example--220v stick welder, 50 amp breaker up stream, and the setting on the machine is say 125amps with a 7018 rod. How can/dose the welder/machine put out that kinda amps with a 50 amp breaker abd not trip it? Ive serched here, but to many non realitive awnswers pop up with the given key words. Could someone please explain it in english for me please.Thanks Pidge.
Reply:The transformer takes the 220v, 50amp input and turns it into 30v, 125 amp output.220x50 = 11,000 watts input30x125 = 3,750 watts outputEasy on the machine at that amperage (there is loss inside the machine too - it's not a one-to-one relationship coming out)Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:^^^^^^exactly...watts=amps x volts. Here's the even stranger factoid: I can power my welder on 6 gauge wire. why do the same number of watts require 2 gauge welding leads? its all about how you arrange the amps and the volts.Last edited by Louie1961; 02-24-2015 at 05:06 PM.Miller Multimatic 255
Reply:Like Dave said, it's basic transformer theory.   In a perfect world, 220v at 30 amps can be converted with a simple transformer to 220 amps at 30 volts.  In reality, the transformers use some huge conductors and are not real efficient.  That's why they may use 11,000 watts of AC to output 4,000 watts at the torch.The inverter models are a bit more efficient.   They use some neat tricks to do the same job of lowering voltage while increasing amps.  They can be over 80% efficient.    My  inverter based TIG welder will output 200 amps while using only 28 amps of 220V ac.Dan----------------------------Measure twice.  Weld once.  Grind to size.MIG:  Lincoln SP100 TIG/STICK:  AHP Alphatig 200X
Reply:Man you guys are fast, thank you. So the trasformer is a "Step Down" type? thats what I gather, thus able to drop the volts and increase the amps? I'll take it thats just the way they work. So from Daves post, when the volts drop the amps increase, and this is the job of the transformer. Sorry for the brain picking, Im just trying to wrap my head around the whole theory of voltage drop with an amp increase. In my limited knowledge..Amps is the "pushing force" correct? Am i wrong by saying 20v with 250amps (from a mig) is bottle necking the voltage and thats where the wire size comes into play? A larger wire allowing more amps to be "bottlenecked" at a low voltage? ahhhhhh im confusing myself now lol.Thanks Dave, Louie, and dbstoo..Pidge.Last edited by Pidge; 02-24-2015 at 05:27 PM.
Reply:Pidge, it's all about power and how it's applied. Amps (current) heats and melts wire. Voltage initiates and sustains the arc.  The combination provides enough energy (heat) and arc force to melt metal together. If you can transform a relatively high voltage to a lower one but still enough to sustain an arc, then you can increase the current to melt the wire."USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:Originally Posted by PidgeIn my limited knowledge..Amps is the "pushing force" correct?
Reply:Amps is the "pushing force" correct?
Reply:davido-Pidge was talking about the electrode wire in that post about "Bottle necking" the voltage." 20v with 250amps (from a mig) is bottle necking the voltage and thats where the wire size comes into play? "and Pidge- yer all over the place with the questions  You first ask about Input wire/Breaker and a Stick machine then move on to a MIg/wire feeder machine addressing you question regarding Mig machine and electrode wire sizes:"The wire feed speed is in direct relation to the amperage at a given wire stickout (length of wire from the contact tip to the arc). The voltage is in the case of a CV (wire welder) the constant and is the length of the arc from the end of the wire to the weld pool, as you change the wire stick out the amperage changes to maintain the weld voltage. A normal wire stick out for short circuit mig welding is 1/4".The following example may help you understand this with .035 ER70S-6 wire and C25 shield gas set at 20 SCFH flow.1/4" wire stickout, volts 17 and wire feed speed 150 IPM = 100 amps3/8" wire stickout, volts 17 and wire feed speed 150 IPM = 50-60 amps due to the resistive heating of the wire between the tip and the arc the weld current drops to the level required to maintain the set voltage.If you were to reduce the stickout to 1/8" the weld current would increase to approximatly 150 amps to maintain the set voltage.Typical min and max ranges of each wire diameter for ER70S-6.024 minimum 30A 15V 105 IPM WFS, maximum 150A 21V 710 IPM WFSoptimum vert. setting 80A 18V 310 IPM WFSoptimum horiz. setting 110A 21V 465 IPM WFS.030 minimum 50A 17V 95 IPM WFS, maximum 200A 23V 600 IPM WFSoptimum vert. setting 100A 18V 235 IPM WFSoptimum horiz. setting 150A 20V 385 IPM WFS.035 minimum 50A 18V 75 IPM WFS, maximum 225A 25V 500 IPM WFSoptimum vert. setting 150A 18V 185 IPM WFSoptimum horiz. setting 215A 22V 415 IPM WFS"http://www.hobartwelders.com/weldtal...ire-Feed-SpeedEd Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:On a MIg machine you do not Increase amps- Amps will increase as a result of the Voltage, Wire & Wire Speed selected.On a Stick machine it is the opposite: You set the Amps on the machine and the Voltage will change at the tip of the electrode to sustain the arc.Ed Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:Now… you kinda have the idea with the *bottle necking: remember this is a Circuit- roundy round the electrical current wants to go. It alway wants to go back to where it started.You are creating a *resistance in its path and just like a regular ol' lightbulb- with resistance you get heat and well Light  and with enough heat you can melt sheite!Ed Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:Great info there Ed! I knew how mig welding worked as far as the relationship between amps and volts but didn't know the reason why stickout affected output. Thanks!
Reply:Oldendum, thank you, lol I had to read your first paragraph to have it sink in (tired), but I undersatand. Thanks.Kelvin, "Volts is the pushing force or pressure. Just as a higher-pressure pipe will squirt water farther (or higher in a building), higher voltage will cross a larger gap. Think of lightning -- it's very, very high voltage. Amps is the current, proportional to the diameter of the pipe. At equal pressures, a larger pipe will deliver more liquid. And a larger diameter wire will carry more current before heating up due to resistance.".....Had it backwards oops. Thanks Kelvin for clearing that up.Davido, Thank you for your explanation.Broccoli, Thank you for the explanation, making more and more sense. Thank you very much. I do appologize for "being all over the place and maybe got side tracked a tad with my own question. And yes I shoulda stuck with one process in the question, I just figured talking AMPS wheather it be stick or wire feed did'nt matter. oops. Sorry man for whats starting to sound more confusing. I apprecheiate the awnswers guys.
Reply:Dont fuss, just use the breaker the welders mfg.says is right.My Lincoln 225s says use 50 amp time delay fuses.My welder was new in 1965.Breakers are called for now.
Reply:My Hobart 210MVP said the same thing. Made in 2010. Actually I think it said to use 35amp time delay breakers! I don't think those even exist. Never seen a 35amp breaker even...John 3:16(2) Miller Pheonix 456(2) Millermertic 252Dynasty 210DXHobart 210MVPDoringer D350 SA Cold SawScotchman 350LT Cold SawWebb 10x50 MillWebb 15x40 LatheGeka Bendicrop Ironworker
Reply:Volts are pressure, or Electro Motive Force EMFAmps are volume, the quantity of electrons pushed by the pressureWatts are pressure multiplied by volumeI offer three choices: Good, Fast, & Cheap. You may pick two.Hobart AC/DC StikMate LXHarbor Freight AD HoodHarbor Freight Industrial Chop SawDeVilbis 20 Gallon, 5 HP Compressor
Reply:Originally Posted by nadogailVolts are pressure, or Electro Motive Force EMFAmps are volume, the quantity of electrons pushed by the pressureWatts are pressure multiplied by volume
Reply:Originally Posted by Louie1961^^^^^^exactly...watts=amps x volts. Here's the even stranger factoid: I can power my welder on 6 gauge wire. why do the same number of watts require 2 gauge welding leads? its all about how you arrange the amps and the volts.
Reply:Originally Posted by Willie BHow do they power a city with conductors the size of your welder leads. It's amperage that limits the capacity of a conductor. When voltage is exponentially higher, the capacity in net power is proportionately higher. In the days of Edison and Westinghouse scrapping it was known that AC power traveled over long distances better than DC. I've spent a lifetime being frustrated that people were spreading a lot of false information. In those days AC traveled better than DC because it could be generated at, or transformed to very high voltage, transmitted over many miles, then transformed down to voltage that could be utilized. Edison's DC system used 90 volts, even with very large cables he was good only in a radius of 1/2 mile.The notion that AC flows better than DC is a fallacy. Very high voltage AC power lines can loose 30% of their generated energy over distance in the forms of magnetic field, and heat. DC at similar voltage will loose only 10%. We now have the technology to use DC power. It's great for the world as less must be generated.
Reply:Originally Posted by MinnesotaDaveThe transformer takes the 220v, 50amp input and turns it into 30v, 125 amp output.220x50 = 11,000 watts input30x125 = 3,750 watts outputEasy on the machine at that amperage (there is loss inside the machine too - it's not a one-to-one relationship coming out)
Reply:Originally Posted by EcondronAre you an electrician? Just curious. You've got a lot of really intelligent posts on electricity.
Reply:Someone here posted a great video of MIG in slow motion. At lower wire feed speed, the wire comes out, contacts the grounded workpiece  where it establishes a complete circuit. It heats because it is the highest resistance conductor in the circuit. It burns off, leaving ionized gas as a conductor until it burns far enough away to cause the circuit to fail. It sputters off, then more wire extends, the process is repeated. The result is a spattery weld, usually cold, with poor penetration.At a higher wire speed, it burns off, but constant feed keeps the arc lit even when the wire isn't touching. It sounds more a hiss than a spatter, or sputter. the frequency of the sound is higher. At a wire feed speed still higher you feel stubbing, it pushes the gun away.The machine will maintain voltage, but amperage changes greatly!An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.
Reply:Originally Posted by Willie B240x50=12,000 or if your supply feeders are long enough, 230x50=11,500 but that would only be at full output. 3,750 watt out might be 5,000 input. (Maybe 6,000 with the Airco). Let this also be instructive to the 110 volt TIG owners welding 1/4" aluminum. It ain't available, but if you had 110 volt supply, and 15 amp current you'll only have 1,650 watts going in. Some is lost in the process, perhaps 1,400 watts to melt metal. A respectable welder needs about 10,000 watts at the filler.
Reply:Originally Posted by dbstooI beg to differ.   10,000 watts at 25 volts is about 400 amps output.   That's Damn Impressive.     300 amps is very capable.   200 amps is respectable.   But the point is well made.   You have to match the welder output to the material (and thickness) that you are welding.   The 1500 watts available from a normal 120 volt outlet @ 15 amps only gives you around 55 amps output after losses. Dan
Reply:Originally Posted by Willie BYou're right with MIG, even aluminum that'd be a bit much. TIG at 35 volts it isn't uncommon.