And when the OP connects his 100 amp charger what will be the effect of using that smaller wire advocated?
I seriously don't get this mind set of sizing wires to the minimum able to handle the loads envisioned. It can't be the cost of the wire as the difference is minimal. Is it a fear of handling larger cables? Are these folks using some type of wire that is hard to work with? The OP will have to configure this once and will be done for the life of the system. Fine strand welding cable is cheap and is easy to work with. A larger cable will provide the most efficiency with charging and may prevent a voltage drop that would interfere with the operation of the inverter.
