yeah, look at the picture of the material you are making. with refiners it will say x11, x12, x13.
or with planks/stone x100, etc.
So, the basic smelter, you need multiples of 100 ore to make 1 ingots per 100 ore.
With the refineries, you need multiples of 1000ore, to make 11/12/13 ingots...