I am currently working on a project where I need variable power between 200 - 250vdc @ 4 - 8 amp range. I have (2) 0 - 140vac @5amp POWERSTAT variable autotransformers. Is there any reason I can not use these together, one each on each leg of my 220ac line connected to my 1000volt-50 amp FWRB powering an inductive load. Would I experience any weird feedback or need any extra components in the circuit to prevent problems ? I have been using 2 cheap Ebay SCR type (triac-diac) type controllers wired in this manner but control is less the desirable and occasionally I fry a triac. Any assistance in improving the control and reliability of this circuit would be greatly appreciated.