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= Inverters and Mains Power in Overland Vehicles =

Modern overland vehicles often combine both 12/24-volt DC and 230-volt AC power systems. An efficient and safely-installed mains power setup allows you to run domestic appliances, recharge devices, and connect to shore power at campsites. This page outlines the principles and best practices for designing **on-grid** and **off-grid** mains systems using inverters, chargers, and safety equipment.

== Overview ==
Vehicle electrical systems normally operate at 12 or 24 volts DC, while household equipment expects 230 volts AC (in the UK/EU). Bridging these two standards requires a power inverter — an electronic device that converts DC battery power to AC mains voltage.

Depending on your travel style, your system may need to support:
* **On-grid hookup:** connecting to campsite or home mains supply via a shore-power inlet.
* **Off-grid power:** using an inverter to provide AC from your batteries, recharged by alternator, solar, or generator.

== Core Components ==
* '''Inverter:''' Converts 12/24V DC to 230V AC. Choose a pure sine wave type for compatibility with sensitive electronics. Common sizes range from 600W (for laptops and chargers) to 2000W+ (for kettles, tools, or induction cookers).  
* '''Battery bank:''' Deep-cycle AGM, Gel, or Lithium (LiFePO₄) batteries supply the inverter. Lithium systems provide higher usable capacity and faster charging.  
* '''Charger or inverter/charger:''' When plugged into shore power, a charger (or combined inverter/charger) replenishes the batteries and supplies onboard AC circuits.  
* '''Shore inlet and RCD/MCB panel:''' A weatherproof inlet connects to campsite power. The line should pass through a Residual Current Device (RCD) and Miniature Circuit Breakers (MCBs) for safety.  
* '''Transfer switch (optional):''' Automatically selects between inverter power and shore power, preventing back-feeding.  
* '''Earthing and bonding:''' Proper grounding is essential. On-grid use ties the vehicle’s earth to campsite supply; off-grid inverter systems should bond neutral to earth at the inverter output to mimic a safe TN-S supply.

== System Layout ==
Typical wiring order:
# Shore inlet → RCD/MCB panel → AC distribution sockets.
# Inverter output → RCD/MCB panel (through transfer switch if fitted).
# Battery bank → Fuse → Inverter DC input (heavy cables, short run).
# Charger → Battery bank (with DC fuse and isolation switch).

Use appropriately rated cables and fuses for all connections. The inverter’s DC side draws very high current — 100A or more for a 1200W load — so ensure short, thick cables and secure terminations.

== On-Grid Use ==
When connected to campsite mains:
* Inverter may automatically bypass to charger mode.
* Ensure RCD protection and correct polarity.
* Use a tested EHU (Electric Hook-Up) lead with a waterproof connector.
* Avoid overloading — campsite breakers often limit current to 6–10A.

== Off-Grid Use ==
When camping remotely:
* Turn off high-draw appliances unless batteries are fully charged.
* Prioritise energy-efficient devices: induction hobs, LED lighting, low-power fridges.
* Recharge from alternator, solar array, or generator as needed.
* Monitor battery voltage or state-of-charge display regularly.

== Safety and Good Practice ==
* Fit fuses, isolators, and RCD protection on all circuits.
* Use marine- or camper-rated cables and connectors.
* Label mains and DC wiring clearly.
* Disconnect power before working on the system.
* Keep AC and DC wiring separate where possible.

== See Also ==
* [[Solar Charging Systems]]
* [[Battery Types and Management]]
* [[12 Volt Wiring and Fusing]]

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''This guide is a general overview; always follow national wiring regulations (e.g. BS 7671) and manufacturer instructions when installing mains systems in vehicles.''