I want to connect a wireless router and ethernet switch to a 12VDC battery bank on a boat. The battery bank DC voltage will usually operate in a range from a low of 11.2 volts to 13.8 volts. There is potentially a risk of voltage or current spike when the engine alternator operates. How can I protect my network electronics so that it received a steady supply of 12 volts (or a range of 11-13 volts)?