Inverter vs Standard - differences?

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Im curious whats the major difference between a standard welder (say tig) and an inverter? I obviously see the size difference, making it more portable - but any other mechanical differences that make one better then the other?Regards,        Rob
Reply:My low level of understanding on this is that the inverter can be "digitally controlled" so that it can resond very quickly and accurately.  So in the case of a pulsed weld, the inverter is absolutely fast and accurate when commanded to hold 300 amps for 5 milli-seconds, and 5 amps for 30 milliseconds.  You can achieve a true "square wave" with totally adjustable frequency.The transformer on the other hand, is limited in its response time by inductance, and can not reach the target pulse current in very short time periods.  A relatively moderate frequencies you cannot get a square wave, it is much more sloping an rounded wave like AC.Also, when AC welding with a transformer, high freqency is needed to maintain the arc, where as with the inverter it is not needed because of the instantaneous switching from DCEN to DCEP.Also, with AC welding on the inverter, a sharpened tungsten can be used for better arc control than you get with the balled tungsten that forms when using the transformer power supply.
Reply:Inverters are Use less electricity by a noticeable amount.  Compare similar size machines for power in and power out.   Inverter should win every time.With AC, you can't beat the adjust ability of a good inverter.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:this being said, for moderate hobby work/ around the house fixer ups - a small inverter would almost be better placed then a 'standard' tig welder?  As of right now im just wanting to get the method of welding down, as well i would like to do some yard art or something along the lines.
Reply:The primary differences are price, power consumption, efficiency, power factor, and controlability.Most of the features you can get in an inverter are available in a non-inverter, but beyond the basics, they will cost a good bit more in the long run, even if the machine has lower up front cost (not all do.)Many features come a lot more readily in the inverter, other come harder... An example is AC: basicly dead simple in a standard transformer machine (just don't rectify the output. The controls are pretty much shared), but requires either a second power supply for the opposite polarity or a very heavy switch bridge in an inverter. Fine low end control is a lot easier in an inverter than a transformer machine, as are a lot of the features such as pulse, since they are primarily software and a few panel controls in a machine that already has a microcontroller (which is all but the cheapest)Transformer machines are no longer any more rugged (I wouldn't expect any transformer machine to survive what I have seen done to an XMT350), but they do have proven low-maintenance, long life. There is a 40-year-old, 600Amp machine in my shop that sees use almost every day. Pulled the dead mice and burnt dust out a couple years ago. It will be due again in maybe 2010. The current generation of lightweight inverters hasn't been around long enough to judge, but indications are quality machines will be able to match up reasonably well over time.In practice, the money saving comes from reduced power use (more efficient supply), better control of the power factor (this can actually be controlled by the supply and maintained at almost exactly one), reduced cost of installation (smaller wire, lower current service, lighter, and smaller), and moderate portability in even a fairly beefy supply (can you imagine carrying around a 125Lb tombstone in your truck for a ten minute job? Ok, how about a Maxstar at 15Lbs (or 30 for the 200A)? How about wiring it in at the job?) Add to that that extension cord is a lot cheaper than welding lead, so if you need to be able to move 100 feet around the shop, the price difference between 100 feet of 8Ga or 10Ga SO cord and 200 feet of heavy welding lead (round trip) may make up much of the price difference between the machines. What about 300 feet in a large shop? What it comes down to, for me, is there are advantages to both styles, and your needs control which is 'better' in a given circumstance. I wouldn't air-arc at 300A with a 350A inverter. It doesn't have the leeway. I will, and have, done it with a 300A transformer machine with no ill effect. I would not buy a transformer machine, at this point in time, if I was planning a production shop with ten machines TIGging at 200A all day long. Inverters, in that case, would probably pay for themselves readily in power savings, reduced installation cost, reduced need for plant environmental control (air circulation, air cooling, etc) demanded in the modern workplace, and flexibility.Wow... Did I have too much coffee today?
Reply:I have a 425 amp Lincoln inverter.  It uses 1/3 less power welding at 250 amps than my wirematic 250.  You can dial in any arc you want MIG, Fluxcore, Stick....  It has a kick A$$ gouging mode.Oh yeah, it weighs 84 lbs.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:I use an older inverter (powcon 300ss and a 300sm) for a lot of my welding.  These are pretty basic no-frills machines by today's standards...however, the arc characteristics are much better than a standard machine on single phase power.  Also, I can run mine at around 200 amps on a 30-40 amp breaker, one my traditional machine would trip at much lower output level.  At about 75lbs each, I can put two inverters in the back of a toyota camry with no problem...my miller dialarc 250...well, let's just say putting that one welder in the back of a camry would be a huge mistake.My 300sm will do stick, mig and tig (dc) all pretty well, because you can switch between cc and cv mode.  My dialarc is only cc, so that limits it a bit in using it for a wire feeder power source...in my opinion, the biggest benefits for the hobby welder is the ability to easily use standard household electricity, and the compact form they typically come in.Smithboy...if it ain't broke, you ain't tryin'.
Reply:*some* inverters are also pretty forgiving on their power source.  I'll use Miller's example, cause that's what I am familiar with.  Pick a voltage between 120 and 460, ( dynasty 200dx for this example ).  got 120v 3 phase, not a problem.  got 208? strip the leads and shove them in the box.  ( just kidding, of course )
Reply:smithboy - i may have to come visit you if your over in carrollton :PThanks everyone for your most appreciated advise and knowledge! Its hard, atleast on first glance, to find anyone around my immediate area with such extensive knowledge. I think I would enjoy finding an inverter that has a little of all my needs (tig/mig/arc), any suggestions there? As well, who makes a solid plasma cutter inverter? There's definitly something that turns heads around my job site. They seem to think the only way to cut is Gas...Rob
Reply:Well, if the Miller Extreme 375 is anything like it's non-inverter cousin; it should be a good unit.  They had one at my local shop, I thought it was a mock up... but it was a real unit.  Something like 18 lbs.