I got one for my 250EX and your right it only went to 230A but the bottom end was OK I put it on my new 255EXT and it works the complete range 3-250 DC and 5-250 AC. I got the slide amperage controller I have been using them for 25 years on my old Hobart 250 and on the old Miller they are long gone now the 400lbs are now take over by the 250EX and 255EXT. I like them in place where you have a hard time using a pedal like on your back or inside a boat or welding places you need your feet for balance you will like them CK is a nice controller.
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