Net Splitter
The net splitter is a device that allows controlling connectivity between subnetworks. Unlike the relay or power converter it directly connects adjacent subnetworks, i.e. components can be accessed. Each side's connectivity can be toggled using a wrench (e.g. the scrench). When a redstone signal is applied to the net splitter, all sides' connectivity is inverted.
This block can therefore be used to toggle connectivity to certain parts of a component network. Use a redstone I/O block or redstone cards to automate the net splitter.