Hi! I just purchase from Everlast Canada a PowerPro 256, is it normal that I received a open unit with the plasma cutter with a burn tip, plus, on the front on the unit a spark (like a short circuit) on the front positive(+) connector and a knob (The nut on the pot) different then the other one? It seems as a demo or a return unit. Are they making test on each unit, before shipping? Thank's for the informations.