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Tig welder output voltage.

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  • Tig welder output voltage.

    Hey guys,

    Look out new guy on the forum!

    Quick intro, I weld as a hobby mostly changing my aluminum boat around. I have high hopes of building one (23-28') from the ground up one day. I also have a Jeep that I build stuff for, as well as other goofy projects.

    Anyways, enough about me.

    I'm getting a Tig welder soon and I've noticed that different welders have different output voltages for the same rated output current. For example the Dynasty 200DX (that I'm going to get soon) has an output voltage of 16V@150A with a 230v input yet the Syncrowave 180SD (yeah I know it's been upgraded, old catalog with pages stuck together. LOL) has an output voltage of 26V@150A for the same 230V input. I realize that these welders use different technology. So, I guess what I'm asking is how does output voltage affect the weld/welding?

    Also, why aren't Tig's rated by capacity like Mig welders? Ya know like 22gauge to 3/8" like my MM210 is?

    One last question I promise!

    Can someone please difinitively answer the generator question for me? I've done a search on it and now I'm even more confused/concerned. Do I really need a Trail Blazer to run my MM210? I don't have the means, the desire yes but I can't justify it. Can some one recommend a more reasonably priced welder to power it? The way I got it figured I need approximately 8000-8500 watts to run it effectively at it's rated output. Keep in mind I'd like to run a Dynasty 200DX off of it as well if possible. (Obviously not at the same time. )

    Thanks in advance for your help,



  • #2
    Welcome aboard:

    For the rating of a machine use this it will help. 1 amp=.001 of material thickness so a recomended max for the D200DX is .200 thick.

    The will run on less power but as soon as you hit something thicker than 1/8" you'll cause it to overheat, it isn't worth it. I've hit the thermal limit on mine only once with full current, with lower input amperage the max comes much quicker, and more often. The voltage differences your seeing are not as great as they appear, differences in technology and construction as well as the output amperage differences make it actually closer than it appears.

    The Dynasty will run on less than the mm210 but the dirtier the power feed the more likely you'll have trouble with consistancy. I've run mine off my friends Bobcat and it did fine but off a generac5KW it wasn't what I would call fun, the surge was easily detectable in the arc.



    • #3
      welcome Capt Sport

      Paul Seaman covered the thickness thing for ya, and the generator a bit as well. if you get a large enough generator to run them they will be OK as they were setup to take a +or- of 10% input fluctuations. it of corse is not the best way to do it but if needed to get the job done it can be done, one suggestion i would make is to adjust the idle up to a running point close to the load point so it doesn't have a big lag at weld start up. this will help keep the power more constant and make it a better power source for the welders.8000-8500 watts should be OK, again you want to keep it as constant as possible i have run my lil MIG off my generator with excellent results by kicking up the idle to keep it running at load speed. it will use more gas and make the generator run harder but if its a good generator it should be fine. my same generator is used to power my house when we have power outages. a rather common thing out here in the sticks and as we are so far out of the town our power concerns are addressed last on the list, so my generator has run for10-24 hrs strait be for with out any problems.its only a 5500 watts so it runs in high draw state the hole time as it needs to power my 220V well water pump, refrigerator, large stand up freezer, house heater, lights, TV., DVD player, well you get the ideal running above the standard idle wont hurt it they set it up to idle low to save gas, so running it at operating speed wont hurt it just use more gas but it will help you get a cleaner power from it.


      • #4
        As far as the arc voltage goes..... Its stated in relation to duty cycle. If your tig welding steel with argon, your AV should be 9 to 11 volts. If your Tig welding aluminum it will be around 10-13. If you are tig welding with helium it will be 19 -23 volts. It you stick weld w/ 7018 it will be even higher - like 26 volts.

        The higher the voltage rating at a certain amperage will directly relate to a better duty cycle. Welders are all rated at the wattage out @ a certain duty cycle.

        So do the math Volts x Amps = Watts

        That would mean that:
        The dynasty = 2400 watts rated output
        The syncrowave = 3900 watts rated output

        But the sync will draw alot more power in than the dynasty.

        hope this helps


        • #5
          I was under the impression that the voltage was the open circuit voltage and that voltage varied to keep current constant. If you ask for 100 amps the arc voltage changes with distance, gas etc to maintain 100 amps??

          Otherwise the actual power output (heat) would change (volts x amps = watts)


          • #6
            Originally posted by Laiky
            I was under the impression that the voltage was the open circuit voltage and that voltage varied to keep current constant. If you ask for 100 amps the arc voltage changes with distance, gas etc to maintain 100 amps??

            Otherwise the actual power output (heat) would change (volts x amps = watts)
            This is basicly how I see it too. The maximum current rating of any TIG machine will require the maximum rated voltage to achieve, but the duty cycle at maximum output will be less than at "rated" output.

            If I use my TA185 as an example, it is rated at 185 amps at 17.4 volts with a 20% duty cycle. However, if it is set for 100 amps, the arc voltage will be 26 volts and the duty cycle is 100%.

            Unlike a GMAW welder, I can only set the current on my TA185. Arc voltage is determined by the machine, depending on the variables I introduce with the way I maipulate (or fail to manipulate ) the torch!

            Them be my 2!



            • #7

              OCV is different than arc voltage. OCV is the output voltage without and arc - in an open circuit condition. It is also different that you High Freq voltage.

              Arc voltage is the actual voltage drop across the arc. There are several factors that contribute to this.

              1 Ioniazation potential of the gas
              2 Actual distance from the anode to cathode
              3 electrode geometry (lesser of an issue)

              Actual heat input will drastically change with a change in either of these 3 items!
              So will the duty cycle of the welder


              • #8
                Originally posted by Laiky
                I was under the impression that the voltage was the open circuit voltage and that voltage varied to keep current constant. If you ask for 100 amps the arc voltage changes with distance, gas etc to maintain 100 amps??

                Otherwise the actual power output (heat) would change (volts x amps = watts)

                Voltage does vary in a CC machine to keep the current steady. However it varies within a range that's dictated by factors such as gas, polarity, etc. Arc voltage changes with distance and does actually change total power output (heat) at the same current level. A long arc length with 100 amps actually makes more heat than a short arc length at 100 amps. This is very important to understand when tigging certain super alloys to spec and it is a skill stick operators learn in order to control the puddle. Does that help?? The rated voltage at rated amperage is a closed circuit voltage and amperage power rating.


                • #9
                  First and foremost let me say a big thanks!

                  I think I understand the difference in output voltage for the different welders now.

                  One last question. Based on the replies a DX 200 won't be enough machine to weld 1/4" aluminum and steel?

                  Even on 230 three phase it wouldn't be enough if the rule of .001 material thickness requires 1 amp output rings true, then it's only good for .200 material. And, I already know that I don'/won't have 3 phase power.

                  Is it really that wimpy as to not even weld 3/16" on single phase power?

                  I guess I need a DX300 to weld upto and including 1/4" aluminum and steel huh? Dam those are $$$.

                  Thanks for the help,



                  • #10
                    Now you understand the basics, lets confuse you really well. Adding helium in mix or pure in place of makes the weld hotter and therfore makes a lower amperage machine weld thicker than the given rating. Doing 1/4" on the dynasty 200DX can be done, BUT--I would not buy this machine for a steady purpose of doing that as it is in excess of the capacaties and it will suffer for the abuse. Have I done it yes do I recomend it absolutely not, it is bound to shorten the life expectancy of the machine, how much no one can tell.



                    • #11
                      he skipped a few words to make it even more confusing,
                      adding helium to the argon or using pure helium instead of argon will get you more heat, also pre-heating will allow for welding thicker material, also the dyn's wave shaping will help focus the heat to help also. but it still comes down to 1/4" being a bummer on the 200DX. if you intend to do it once in a wile you would be ok, also prep and multi pass is a good option but as you are welding on the top end of the welder your duty cycle would be very short.
                      ..if you have a lot of 1/4" and up then it really would be better to step up to the syncowave 250 or the dyn300DX. a nice used synco250 would be a better $$$ if thats a consideration.
             of the other members is about to sell one of his sync.250's you might get with him on a deal.
                      I'll find his post for ya.


                      • #12
                        catch him and see what he is looking for on the one he lets go.



                        • #13
                          Well, I don't have a lot of work in the 1/4" area. At least not the kind that require tig over mig. And, my MM210 can handle most of the non tig required work.

                          So, I guess the next logical question is how is the DX200 on 3/16" using 220-230V single phase power? (aluminum & steel) 90% of what I work on is/will be less than 3/16". Is this the machine for me? Mostly aluminum at 3/16" thickness.




                          • #14
                            i would say in that case the dyn.200DX would work well as a MM210 partner. add a spool gun to the MM210 for thicker aluminum and you should be good to go.


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