YOUR ENERGY PROFILE.
This document contains the sizing of your future electrical installation, calculated based on your appliances.
Inventory:
Battery
To guarantee 0WH without damaging your bank (80% max discharge):
Solar
Minimum power required to recharge your consumption:
220V AC
Maximum power (with 25% safety margin).
12V Cable Sizing Guide
Use this professional reference table to select the correct gauge (mm²) for your cables. For 12V in a van, the maximum tolerated voltage drop is 3%. Always use multi-stranded flexible automotive wire.
| Current (A) | Round trip < 2m | Round trip 4m | Round trip 6m |
|---|---|---|---|
| 5A (LEDs, USB) | 1.5 mm² | 2.5 mm² | 4 mm² |
| 10A (Fridge, Pump) | 2.5 mm² | 4 mm² | 6 mm² |
| 20A (Heater) | 4 mm² | 10 mm² | 10 mm² |
| 50A (DC/DC Booster) | 10 mm² | 16 mm² | 25 mm² |
| 100A (Inverter) | 25 mm² | 35 mm² | 50 mm² |
Fuse Sizing
The fuse protects the wire, not the appliance. Always place it as close to the power source as possible (battery or busbar).
- Wire 1.5 mm² → Max fuse 10A
- Wire 2.5 mm² → Max fuse 20A
- Wire 4 mm² → Max fuse 30A
- Wire 6 mm² → Max fuse 40A
- Wire 10 mm² → Max fuse 60A
SCHÉMA ÉLECTRIQUE
PANNEAUX SOLAIRES
0W
REGULATEUR MPPT
BATTERIE AUXILIAIRE
0 Ah
Lithium LiFePO4
BOÎTE À FUSIBLES 12V
Pompe, Leds, Frigo...
CONVERTISSEUR 220V
NON REQUI
SHOPPING LIST
Where to find this equipment? Here is the community-approved selection.
12V 6-way Fuse Box
Mandatory protection
Digital Multimeter
Test your connections
Heavy Duty Crimping Tool
For perfect lugs
Heat Shrink Tubing
Insulation and safety
Comparison table
| Inverter | Wave type | CPAP OK | HiFi OK | Best for |
|---|---|---|---|---|
| Victron Phoenix | Pure sine | ✓ | ✓ | All loads |
| Renogy 2000W Pure | Pure sine | ✓ | ✓ | Mid budget |
| Cheap modified sine | Modified | ✗ | ✗ | Tools only |
| Giandel 2000W Pure | Pure sine | ✓ | ▲ | Good value |
About this tool
Pure Sine Wave Inverter for RV and Van: How to Choose the Right Size
Choosing the wrong inverter size is the most common and most expensive electrical mistake in van builds. This guide tells you exactly how to size a pure sine wave inverter for your specific loads.
Why Pure Sine Wave and Not Modified Sine?
Modified sine wave inverters (cheaper) produce a stepped waveform that causes problems with sensitive electronics: laptops overheat, motors run hotter, audio equipment hums. Pure sine wave produces the same smooth waveform as mains electricity. For a van, always use pure sine wave.
How to Calculate Required Inverter Wattage
Step 1: List every 230V appliance you plan to run simultaneously (worst case) Step 2: Sum their wattages Step 3: Add 25% safety margin for startup surges
Example for a remote worker:
| Appliance | Running Watts | Startup Surge |
|---|---|---|
| MacBook Pro 16" charger | 140W | 140W |
| External monitor | 30W | 30W |
| 230V desk lamp | 20W | 20W |
| Kettle (occasionally) | 2,000W | 2,200W |
| Total (kettle on) | 2,190W | 2,390W |
→ Need a 2,500W pure sine inverter minimum (3,000W recommended for safety).
Recommended Inverter Sizes for Van Builds
| Build Profile | Max Load | Inverter Size | Example Model |
|---|---|---|---|
| Basic (laptops only) | 300-600W | 1,000W | Victron Phoenix 12/1200 |
| Remote worker | 1,000-1,500W | 2,000W | Victron Phoenix 12/2000 |
| Family / kettle / microwave | 2,000-2,500W | 3,000W | Victron Multiplus 12/3000 |
| High power (air con) | 3,000-5,000W | 5,000W+ | Victron Quattro |
Inverter-Charger vs Pure Inverter
If you plan to use shore power (camping sites), a Victron MultiPlus inverter-charger does double duty: it inverts 12V battery to 230V, AND charges your battery when connected to shore power. One device replaces: inverter + standalone charger. Highly recommended for any serious build.
Critical Cable Sizing for Your Inverter
A 2,000W inverter draws ~167A at 12V (2,000 ÷ 12 = 167A). This demands 70mm² (2/0 AWG) cables at 500mm or less between battery and inverter. Under-sized cables here are where van fires happen.
Expert tip: Your inverter's battery cables should be as short as physically possible — aim for under 500mm (20 inches). Every extra 100mm of cable adds resistance that causes voltage drop under heavy load and can trigger inverter low-voltage shutdown.