It's a Schumacher, 20-40-225. I keep it on 20 amps, but it runs more or less depending on the size of the iron and the distance to the scrap piece. Big Dutch oven bottoms (#9 and larger) for instance, will run at 35 amps because I surround them with a metal bowl. I just installed the new cables last night and ran a no 8 Dutch oven at 25 amps today for about 8 hours--heat was fine and the oven came out clean. To answer the other question, it could well be that some of the wire strands were broken further into the cable where I couldn't detect it. When I cut off the "burnt" strands (there would literally be some that were ash), I always cut back to good wire, then reattached the clips. At any rate, the charger came with 6 gauge wire and I replaced them with 2 gauge. I still need to put in some new strain reliefs, but it's running fine at the moment.