If you replace a machine with the same machine of the same quality (other than normal) it will increase the quantity of the machine in your inventory.
Bug effects this version and QEF2 but not Andreys version witch has its own issues.

When trying to place a machine with a quality higher than normal, it is not spent from the inventory. If it is placed by a robot from the logistics network, the machine is added to the player's inventory, this happens even if I am on another planet. This only happens with those machines to which the mod adds additional module slots.