The vcc device has an associated label (defaulting to ``vcc'') which can be changed by the user by selecting the label and pressing the label button in the side menu. All nodes connected to a vcc device with the same label are taken as being connected together. The label of the vcc device is also used to name the net when node mapping is active, as set with the nodmp button in the side menu.
This will not tie nodes between the main circuit and subcircuits, or between subcircuits, unless the terminal name is also defined in a .global line for SPICE. If not global, then it will only tie together the nodes of each subcircuit, and the main circuit, due to the modification of node names that occurs during subcircuit expansion. The .global line prevents this modification, and can be added as a spicetext label.