ECN Forum Forums General Topics of the Trade General Discussion Area Canada vs. USA.Parrallel runs in the same conduit

To Canadian code, install a 376 amp service, and the next fuse size is 400 amps in Table 13.

I don't understand the relationship between the size and ampacity of 500 mcm and 4/0. Isn't 500 mcm more than twice the size of 4/0 and less than double the ampacity?