Build a Load List First
List every electrical device, its voltage, approximate power draw and daily run time. Lights and fans may use little energy, while induction cooking, electric water heating or air conditioning can dominate the system design.
12V DC Is the Core of Most Camper Systems
Common 12V loads include lights, fans, water pumps, USB outlets, refrigerator controls and diesel-heater electronics. These circuits require correctly sized conductors and overcurrent protection based on current, length and installation conditions.
120V AC Usually Comes From Shore Power or an Inverter
US household-style outlets and appliances use 120V AC. In a van, AC power may come from a campground connection, an inverter connected to the battery bank, or a combined inverter/charger. Grounding, bonding, GFCI protection and transfer behavior are safety-critical and should comply with applicable codes and equipment instructions.
Charging Can Come From More Than One Source
Solar, alternator/DC-DC charging and shore-power charging can all replenish the battery bank. The charge profile must match the battery chemistry and the components must be compatible with one another.
Protection and Disconnects Matter
Fuses or breakers protect conductors from excessive current. Main disconnects, branch protection and accessible service points make the system easier to isolate and troubleshoot. Never rely on the appliance alone to protect a cable.
Document the Final System
Keep a wiring diagram, fuse schedule, conductor notes and component model numbers in the van. Electrical work can cause shock, fire or equipment damage; use a qualified professional for work beyond your training or where local rules require it.
Turn the research into a build plan
The free guides on this site explain individual decisions. The Van Conversion Manual is designed to keep the major systems organized in one complete digital reference for the project.