redcane wrote:I don't think it is the main drive fuse itself - 280A 300V is a lot of power to not notice the smoke come out somewhere.]
I agree it would be unlikely for the main drive fuse to blow from what you've described, but a quality 300 amp fuse could easily blow without anything being noticeable beyond the loss of power.
I had an EV conversion in a commercial fleet, and the newby driver got stranded when "seeing what it could do" up our longest, tallest local highway hill. Main pack breaker was good, but a bare metal 400A fusible link within the pack had had opened up only a foot behind the driver's seat, leaving a big smoke stain in the lexan tube that had contained it. Neither the driver nor his passenger recalled hearing or smelling anything...
Personally, I like lexan covers in DIY battery packs. Besides clearly allowing easy inspection, the Lexan will begin to melt, bubble and release a potent acrid smell long before you'd notice a loose terminal or other 'hot spot' via the gauges, but it doesn't burn easily (or sustain a flame- ask how I know!).