Transformer vs generator

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I haven't been able to weld yet with my newly aquired Weldanpower due to being busy & shop not done yet, but I have read where an engine driven welder welds smoother than a transformer type. My Weldanpower is DC and my Thunderbolt is AC/DC, will I notice a difference welding with the Weldanpower vs the Tbolt on DC? Does the Weldanpower produce the DC current differently than the Tbolt?ThanksMiller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.
Reply:The Weldanpower is an AC alternator power source, but they're a smooth and powerful welder;  not in the same league as "pure" DC generator, but definitely above a "buzz box."Good Luck
Reply:Here's my view on how this works... (and I could be wrong.)In DC stick welding the 'smoothness' of the arc is related to how well the welding machine holds the welding current 'constant' - with variations in arc gap, changes in rod angle, etc.  In old technolgy welding machines, like DC generators, alternators + diodes + inductor, transformer welders + diodes + inductor, the smoothness of the arc is dominated by the inductance controlling the arc.DC generator: The windings of the generator are mechanically connected to the electrode and work piece and the winding inductance serves as a resevoir of stored amps to hold the current constant.Alternator:  The alternator produces AC.  Diodes are used to convert that AC to DC.  However, the diodes form a barrier preventing much of the inductance in the alternator windings from influencing the arc.  To smooth the arc, a large external inductor is placed after the diodes.Transformer: Much like the alternator, the transformer produces AC.  Diodes are used to convert that AC to DC.  However, the diodes form a barrier preventing much of the inductance in the transformer windings from influencing the arc.  To smooth the arc, a large external; inductor is placed after the diodes.The importance of inductance in maintaining a smooth arc was driven home to me by trying to weld with a large bank of batteries.  Batteries produce pure DC, no 120 cycle humps of voltage and current like the generators, alternators or transformers.I thought that with batteries as the power source, I could produce a really smooth arc - NOT SO!  There is little current control.When I struck the arc, a massive surge of current would blow the end off the rod!  The arc, once established, was difficult to maintain with variations in arc gap.Why?It's all realated to batteries being a constant voltage not a constant current power supply.Changing the arc gap, changes the resistance of the welding circuit and with the constant voltage battery supply, this directly changes the current in the arc = the arc is not smooth!Also, the Open Circuit Voltage (OCV) of the battery power source was either 24 or 36 volts, depending upon how many 12 vollt batteries were used.  Generators, alternators and transformer welders usually all have much higher OCV - like 60 to 90 volts.  The high OCV helps maintain the arc when the arc gap gets large.I added a large inductor between the battery bank and the electrode.  Things changed markedly for the better.  The inductor acted to restrict rapid changes in current flow.  On striking the arc, I no longer blew the end of the electrodes because the inductor prevented a rapid current increase.  When welding, the inductor supplied more or less current to maintain constant current with variation in the arc gap = smoth the arc.Anyway, that's my take on 'smooth arc' - what happens and why.Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:The ranger and weldanpower use the same DC choke and it is pretty good size.  i changed one out in a ranger 8 i bought using a weldanpower parts machine.   there is definitely a difference in smoothness from the damaged choke to the good one.   being that the choke weighs about as much as your whole thunderbolt, i am sure u will see a somewhat smoother arc but nothing like a pure DC current machine like a SA200 etc.   on the weldanpower you are still going through rectifiers (diodes) to get from AC to DC.. (the condensed version of RIck's answer)Tiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:There's also a difference between alternator engine drives.  If the engine drive produces 3 phase AC and the rectifies and filters it, you'll get less ripple (with the same amount of filtering) than from single phase.It really doesn't matter though.  If you have enough filtering you can make any of them as smooth as you want.  The trouble is the filter may be the size of refrigerator and cost several thousands of dollars.  Like everything else, the welder manufactures just make it 'good enough' so they can keep the cost down.Dynasty200DX w/coolmate1MM210MM VintageESAB miniarc161ltsLincoln AC225Victor O/A, Smith AW1ACutmaster 81IR 2475N7.5FPRage3Jancy USA1019" SBAEAD-200LE
Reply:Thanks for the responses, I just can't wait to start using it. Looks like it will be another 2-4 weeks before my garage/shop will be ready, I can't put anything in it yet untill I get the overhead door installed, and I still need intermediate inspection, insulation & wall/ceiling sheathing before the door can go on.At night when I am lying in bed I think about her, (the weldanpower that is) out there under a blue tarp chained to my back porch.Miller Challenger 172Miller Thunderbolt AC/DC 225/150Miller Maxstar 150 STLVictor 100CVictor JourneymanOxweld OAHarris O/ASmith O/A little torchNo, that's not my car.