Basically yes, but as you have two batteries in parallel this reduces the inductance. Your setup only adds a few cm for your Y cable, so this is more or less the stock configuration. I am a bit puzzled about the unit reporting overcurrent while displaying only 1328 amperes, but the overcurrent (naturally) looks for maximum, while the display is an average value - and the current ramps up first, over a period of a few hundred microseconds. Please discharge the batteries to 3.8V, and try again. The lower voltage helps keeping the current below the 2000A limit. You can then ramp it up again during normal welding, the extra resistance of the weld spot helps in this situation.
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3.8v per cell? Im using 3-cell (11.1v) Lipos in parallel.
3.8v x 3= 11.4 volts per 3 cell pack each.
Im still having problems with my unit, today I tried running it with a lead acid battery and i still get overcurrent… I messured my cables to exact 3m. 
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3 meters of cable is excessive, and results in significantly allowed current due to inductive kickback as I describe in the operating manual. If you want to use the unit to its full extent, then I suggest to reduce the cables to their absolute minimum. Only at 1.0 meter total you can go all the way up to 2000 amperes.
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Now total cable length is 1.4m . Is my unit faulty or something?
You can see from the graph on page 8 of the operation manual that this is exactly the unit’s limit at this cable length (~1650 amperes). There is nothing wrong with it, your battery is just pushing more current than what’s allowed in this configuration. What model is that? It looks fairly large.
The battery is 92Ah. So what do I have to do to get the calibration correct?
I made one cable a bit longer so total 2,2m and got Overcurrent at 1257A. Something is weird.
have you read and understood what I write in that section in the operating manual? At 2.2m this is the maximum allowed current. You only get the full 2000A when you reduce the cables to 1.0m total. And again, what is your battery model? Just 92AH doesn’t tell me much.
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Its a Powersafe 12V92F. Im not looking for the full 2000A, just trying to get through the calibration. I only get the calibration to work using one 6Ah Lipo.
Rephrasing.
Some batteries can supply too much current. Yours is.
While there’s a limit of 2000amps. There’s another limit based on the lengths of the cables. Longer cables will lower the limit.
Basically there’s a balance going on trying to find a setup that can deliver enough power to weld and not too much to cause other issues.
It is explained in the manual but it’s in depth I had to read it a few times. and I still need to again to understand the inductance part better.
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well said, sir, and I’ll add one to that:
@filipandre if this is your battery, it’s just too big. That much amperage may make the cable length irrelevant. A single small/medium car battery should work, or tear into that pack and use, say half of it…
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Okay i think i understand this now, hopfully the Lipo i ordered is perfect 
thank you @tatus1969 @fessyfoo @iamasalmon
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That datasheet number cannot be used directly, as the welder also adds approximately 3 milliohms of resistance (using only the stock cables) and thus lowers the flowing current. But this datasheet also tells the terminal resistance: 5.19 mOhms. At 12V, this would result in I = U / R = 12 / (3e-3 + 5.19e-3) = 1465 A, which would be spot on. As he is getting 1648 A instead (with even longer cables), the real battery’s internal resistance is apparently even lower. There is a corresponding footnote in the battery datasheet “** Resistance values are for reference only and not intended to represent an Ohmic Value or Baseline measurement”. But still I think that the battery is suitable, he just has to reduce the cables to the stock 1.0 meter.
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Dudes, I’m having stupid amounts of trouble fitting this dang 8awg into the xt90. Any tips are greatly appreciated! 
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I find that tinning the wire before stripping keeps the wire nice and tight. I think the bundle of 8awg just barely fits in the xt90 if you do this right. if not, well a little file action should do the trick 
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cut some of the strands if it’s seeming impossible.
I know the advice for soldering is to always to tin but if I tin either side it then it does not fit anymore
I like to put the wire in untinned and just blast it with heat flux and solder until its set nicely. The wire is pre tinned so why need to tin it again? lol
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I’ll tin wire for the heat.
sometimes when working on stuff this thicc, I try to work quickly so that the tinned ends are still warm when I join. Makes things go quicker and it’s easier to get that clean silvery look compared to cold parts 
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