Dynapower Corp. rectifier issues

[Sstephens816]

Hi all, I work at a chrome plating facility that plates bumpers for the big three. We have a dynapower rectifier input 460volt/3ph/60hz output is 12 volts 6000 amps and I’m guessing it’s circa 1968-1973 ish. It is a master slave set up and the problem we have had is the thyristor fuses blowing. While investigating with our 70 yr old electrician(I’m just a mechanic with limited electrical exp.) I noticed in our slave unit when I was checking temps with a temp gun, I noticed our 3 and 4 diode banks were approaching 200degrees as well as the center coil of the transformer. Everything in the master was at its normal operating temps, nothing above 100 degrees, and every wire is correct, everything is installed as it should be on the banks, and tight. My question is could this be an issue with the coil that is connected to the those two banks, and if not any ideas on why this is happening?