Minecraft: 1.11.2
forge-1.11.2-13.20.0.2296
StevesCarts-1.11.2-2.2.2.12
RebornCore-1.11.2-2.14.2.94-universal
No other mods installed.

If I take something like Oak Wood and click on either slot of the Smelter/Advanced Smelter nothing happens. It doesn't matter if the cart has power and the raw materials in it's inventory, neither smelter functions at all.