just consider that your plasma cutter have L1 and L2 and ground...
in 120V mode it's just Hot (L1) Neutral(L2) and ground...
in 240V mode, it's Hot (L1) Hot (L2) Ground...
as long as you got the ground correct it doesn't matter which is neutral which is hot... just consider it L1 L2... because you probably have an inverter unit.. it will take the AC and convert it to DC then inverted or converted it down to the High AMP low volt....
the Cut520D is like that for me...
as well as the Dynasty200D except this one also takes 3PH as well as 1PH... so it has L1 L2 and L3 and ground... with L3 not used normally in 1PH...
anyways... you'll have to tell us which 220V plug you are using or convert to / from... if you are looking for more info...
take a look at this link and see what you have or planned to have...
https://en.wikipedia.org/wiki/NEMA_connector
^^^
for example, I decide to have regular L14-30P as my normal dual voltage welder plugs since it's what most generators uses as well... . and I have a pigtail to convert L14-30R (240stuf)to NEMA 5-15P (120V stuff) ...
in the pigtail I just connect ground to ground... L1 of the L14-30R to the Hot (L1) of the 5-15P and L2 (the other hot of L14-30R) to the neutral leg of the 5-15P...Neutral on the L14-30R is not used... it's not a standard, so you'll have to make sure this pigtail stay with your machine only... .
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