Sorry I do not have the fuse values for all the Joule gear committed to memory... (plus the amps rarely blow fuses unless something is (very) wrong) with the wide range of amps and preamps made over the years, I need to look this stuff up or check actually gear. Jud was not the greatest with some of his documentation which does not help.
I pulled a VZN-100 manual (from a MK3/IV OTL) from the pair I have for sale right now ... a pair of VZN-100's has SEVEN fuses. Main power fuse (on Variac unit) which you may find to be a 10A to 15A slow blow. Then on the back of each amp chassis there are two B+ fuses (3A fast blow) and one "8 to 10 amp" (yes, that is what the manual says) slow blow on the filament string power input IEC on the amp chassis.
Now this is ONLY for a VZN-100, the values are most likely different for VZN-80, VZN-160 etc etc.
My preamp manual(s) I have do not list the power fuse size at all (and I have never had to replace one). I had to pull the fuse from my LA300ME to see it is a 2A Fast blow (small size type).
Other info on Joule-Electra gear (product literature, old Joule show hand outs and white paper type info, a number of old reviews and old prices lists) can be found on my Joule-Electra info/resource page: http://sigsound.com/classic-product-info/joule-electra-info-page/