Michael, Bart, all: I took a look at the littlefuse catalog this A.M. and vitrually every fuse in it (fast or slow blow) is listed to hold 135% of the rated current for as much as 1 hour. At 140% the time would be somewhat less, but still many minutes. How long did you leave it run at 42 A? - Mike > It's the fuses not blowing which raises the questions. > Bart