⭐ Choosing an Inverter for Your Campervan

A simple guide to selecting the right inverter for your electrical system.

1. What an Inverter Actually Does

Your leisure batteries store DC power (12V or 24V).
Many household-style appliances run on AC power (230V).

An inverter converts 12V DC → 230V AC, allowing you to run mains-powered appliances like:

• Laptop chargers

• TV / monitors

• Blenders & small kitchen appliances

• Hair dryers (with limitations!)

• Power tools

• Coffee machines

But the type and size of inverter you choose matters more than most people expect.

2. Pure Sine Wave vs Modified Sine Wave

Not all inverters produce the same quality of AC power.

✔ Pure Sine Wave (recommended)

• Produces clean, stable power

• Safe for sensitive electronics

• Works with everything

• More efficient & longer-lasting appliances

• Slightly more expensive

Best for: laptops, TVs, fridges, induction hobs, any modern electronics.

✔ Modified Sine Wave

• Cheaper

• Noisy power output

• Not suitable for sensitive devices

• Can damage chargers, tools or appliances

• Causes buzzing in audio equipment

Best avoided.
We always recommend pure sine wave inverters for campervan electrical systems.

3. Choosing the Right Size (Wattage)

Your inverter must be big enough to run the largest load you expect at one time.

Step 1 — Identify your appliance wattage

Every appliance lists its power use (W). Examples:

• Laptop charger: 60–120W

• TV: 40–100W

• Blender: 300–600W

• Air fryer: 1200–2000W

• Microwave: 800–1500W

• Induction hob: 1500–3000W

Step 2 — Add together any loads you’ll run at the same time

Example:

• Laptop (60W)

• TV (80W)

• Router (10W)

Total = 150W → a 300W inverter is plenty.

Example (kitchen use):

• Blender (500W)

• Coffee machine (1200W)

Total = 1700W → choose a 2000W inverter.

Step 3 — Add 20% headroom

This prevents overloading and extends inverter life.

4. Consider Surge / Peak Power

Some appliances draw a big burst of power when they turn on.

Examples:

• Power tools

• Motors

• Compressors

• Some microwaves

• Induction hobs

If your appliance says:

1500W continuous, 3000W peak

Then you need an inverter capable of at least 3000W surge.

5. How Inverters Affect Your Battery Size

This is the part most people misunderstand.

Running a 2000W appliance from a 12V battery bank requires:

That is a huge current draw.

Recommended battery setups:

⚠️ Lithium batteries are strongly recommended for anything above 1500W because they can safely provide high current.

6. Should You Hardwire or Use Sockets?

✔ Option 1 — Plug-in style

• Inverter has built-in sockets

• Easy to install

• Good for small systems

• Lower risk

✔ Option 2 — Hardwired to a consumer unit

• Cleaner installation

• Lets you power multiple sockets around the van

• Must use an inverter changeover switch

• Needs RCD/MCB protection

• Better for high-power systems

7. Safety Essentials

Your inverter wiring must include:

✔ Correct cable size (use your Cable Sizing Tool!)
✔ Properly rated fuses or breakers
✔ Thick battery cables (25mm²–70mm² depending on wattage)
✔ Ventilation — inverters generate heat
✔ Secure mounting away from water and gas lines

8. What We Recommend

For most conversion customers:

⭐ 1000W Pure Sine Wave Inverter

• Runs laptops, TVs, chargers, small kitchen devices

• Works well with a 200Ah battery bank

⭐ 2000W Pure Sine Wave Inverter

• For blenders, coffee makers, small microwaves

• Requires lithium and 300–400Ah battery capacity

⭐ 3000W Pure Sine Wave Inverter

• For induction hobs / high-power appliances

• Requires a large lithium bank and heavy cables

9. What Size Cables to Use for Your Inverter

Because inverters draw extremely high current from your batteries, using the correct cable size is critical for both performance and safety. Undersized cable can cause:

• Voltage drop

• Overheating

• Fire risk

• Inverter alarms / shutdowns

Use this table to select the correct cable based on inverter wattage and battery voltage.

🔌 Recommended DC Cable Sizes (Battery → Inverter)

(Assumes cable run of 1–2 metres. For longer runs, increase cable size.)

12V Systems

24V Systems

(Half the current = smaller cable possible)

🔥 Always Fuse the Inverter Cables

Install a fuse at the battery end, sized for the expected current:

Use MEGA fuses or Class-T fuses for high-power systems.

⚡ Cable Run Length Matters

If your inverter is more than 2m from the batteries:

➡ Increase cable size by one step
Example:
35mm² becomes 50mm²
50mm² becomes 70mm²

Short, thick cables = better efficiency and less heat.

✔ Best Practice Summary

• Keep cable runs short and direct

• Always mount the inverter close to the batteries

• Use crimped lugs + heat shrink

• Always fuse the positive cable

• Always match your cable size to BOTH inverter wattage and cable length