EHU (Electric Hook-Up) Explained for Campervans

Electric hook-up (EHU) is the simplest way to get mains power into your campervan. You plug a cable into a campsite bollard and suddenly your van has 230V electricity — just like a house. But there is more to it than just plugging in. You need the right inlet, the correct cable, appropriate safety devices, and an understanding of power limits to use EHU safely and legally in the UK.

This guide covers everything you need to know about EHU as part of your campervan charging system, from how it works to what to install and how to avoid tripping the site breaker at midnight. If you want to understand how hook-up fits alongside solar and alternator charging in your build, the VanPower calculator models all three sources together.

What Is Electric Hook-Up?

EHU is a 230V AC mains connection provided at campsites, caravan parks, and some overnight parking areas. In the UK, the supply is delivered via a blue CEE 16A connector (also called a Ceeform or IEC 60309 plug) mounted on a post or bollard.

When you connect, you receive a supply of up to 16A at 230V — that is 3,680W of power. Some sites provide only 10A (2,300W), and a few premium sites offer 20A or more. The amperage is usually displayed on the bollard or stated in the site's booking information.

What You Get from EHU

With a 16A hook-up, you can run:

A battery charger to replenish your leisure battery
230V sockets for laptops, phone chargers, and small appliances
A low-wattage kettle or toaster (up to about 1,500W on a 10A supply, 3,000W on 16A)
A fan heater on a low setting (typically 1,000W)
A mains-powered fridge (if fitted)

What you usually cannot run on a 10A supply without tripping the breaker:

A domestic kettle (2,200-3,000W)
A full-power fan heater (2,000W+)
Multiple high-power appliances simultaneously

What You Need to Install

1. Shore Power Inlet

A blue CEE 16A inlet (male) is mounted on the outside of your van, typically on the side near the rear. This is the socket that your hook-up cable plugs into. It should be:

IP44 rated or higher (splash-proof)
Mounted with a weatherproof cover that closes when not in use
Positioned away from gas drop-out vents and filler caps
At a height that avoids puddle splash (at least 300mm from the ground)

Quality inlets cost £10-£25. Brands like Mains Hook Up, Pennine, and CBE make reliable units.

2. Hook-Up Cable

The hook-up cable runs from the site bollard to your van's inlet. In the UK, you need:

Connector: Blue CEE 16A plug on the bollard end, blue CEE 16A coupler on the van end
Cable type: H07RN-F 2.5mm² three-core (live, neutral, earth) in orange for visibility
Length: 25 metres is standard (some sites have bollards far from pitches)
Rating: Must be rated for outdoor use and at least 16A

Pre-made cables from reputable suppliers cost £30-£60 for a 25m length. Do not use a standard domestic extension lead — it is not rated for outdoor use, not weatherproof, and does not have the correct connectors.

Never Use a Domestic Extension Lead

Standard UK household extension leads are not suitable for EHU. They lack the correct CEE connectors, are not rated for outdoor use, and the cable is typically only 1.0mm² or 1.25mm² — insufficient for the currents involved. Using one is a fire risk and potentially lethal in wet conditions. Always use a proper caravan hook-up cable.

3. Consumer Unit (RCD + MCBs)

Inside the van, the incoming mains supply must pass through a consumer unit containing:

RCD (Residual Current Device): Trips within 30ms if it detects a current imbalance (earth leakage), protecting you from electric shock. A 30mA RCD is mandatory.
MCBs (Miniature Circuit Breakers): Protect individual circuits from overload. Typical van setups have one MCB for sockets and one for the battery charger.

The consumer unit should be installed in an accessible but protected location inside the van. We cover this in detail in our consumer unit wiring guide.

4. Battery Charger

A mains-powered battery charger converts the 230V AC from hook-up into DC to charge your leisure battery. Popular options for campervans include:

Victron Blue Smart IP22 30A (~£130): 30A output, Bluetooth monitoring, excellent multi-stage profile
Victron Blue Smart IP22 15A (~£95): Sufficient for smaller batteries
Ring RSCDC30 (~£80): Budget option, reliable but fewer features

The charger connects to the 230V supply via the consumer unit and outputs DC to your leisure battery.

5. 230V Sockets (Optional but Recommended)

If you want to plug in mains appliances inside the van, you need 230V sockets wired through the consumer unit. These should be double-pole switched and ideally rated for mobile installations. We cover socket wiring in our 230V sockets guide.

Start Simple, Upgrade Later

At minimum, all you need for EHU is an inlet, a consumer unit, and a battery charger. You can add 230V sockets later. Many van lifers start with just the charger and plug appliances into the inverter via 12V when they need AC power.

How to Connect at a Campsite

The connection procedure matters for safety:

Uncoil the cable fully. A coiled cable under load can overheat. Lay it out straight or in a wide figure-eight.
Connect to the van first. Plug the coupler end into your van's inlet before touching the bollard end.
Then connect to the bollard. Push the plug into the bollard socket and twist to lock. The bollard's RCD should be in the ON position.
Check the polarity. If you have a polarity tester (recommended, about £10), plug it into a socket inside the van to verify correct live/neutral/earth connections. Some older sites have reversed polarity.
Test the RCD. Press the test button on your consumer unit's RCD. It should trip instantly. Reset it.

To disconnect, reverse the order: bollard first, then van.

Dealing with Reversed Polarity

Some UK campsites (especially older ones) have reversed polarity on their bollards — the live and neutral wires are swapped. This does not affect most appliances, but it means your MCBs and switches may not break the live conductor, creating a safety risk.

Solutions include:

A polarity checker plug (about £10, plugs into any socket and shows if polarity is correct)
A crossover adapter (swaps live and neutral, about £15)
Wiring your consumer unit with a double-pole main switch that breaks both live and neutral regardless of polarity

UK Power Limits and What You Can Run

10A Supply (2,300W)

Many UK campsites provide 10A. This limits you to about 2,300W total across everything you plug in. In practice:

Battery charger (30A = ~500W) + fridge (100W) + laptop charger (65W) = 665W. Fine.
Battery charger (500W) + low-wattage kettle (1,000W) = 1,500W. Fine.
Battery charger (500W) + domestic kettle (2,200W) = 2,700W. Trips the breaker.

16A Supply (3,680W)

A 16A supply gives more headroom:

Battery charger (500W) + kettle (2,200W) + fridge (100W) = 2,800W. Fine.
Battery charger (500W) + fan heater on high (2,000W) + kettle (2,200W) = 4,700W. Trips the breaker.

Managing Your Load

The golden rule: never run two high-power appliances at the same time. Boil the kettle, then turn it off before switching on the heater. A simple habit that avoids embarrassing trips to the bollard in the dark.

Low-Wattage Appliances Save Headaches

Invest in a low-wattage kettle (1,000W), a low-wattage toaster (700W), and a low-wattage hair dryer (1,200W). These are designed for caravan and camping use and dramatically reduce the chance of tripping the site supply. They cost a little more but are worth every penny.

EHU Costs at UK Campsites

Electric hook-up is rarely free. Typical UK pricing:

Club sites (Caravan and Motorhome Club, Camping and Caravanning Club): EHU included in the pitch price (£20-£35/night)
Private campsites: £3-£8/night extra for EHU, or included in premium pitches
CLs and CSs (small sites): Often £10-£15/night with EHU included
Some wild camping areas and farms: No EHU available at any price

Over a two-week trip, paying £5/night for EHU adds £70. Compare this to the free electricity from solar and alternator charging — one of the financial incentives for investing in a self-sufficient electrical system.

EHU and Your Broader Charging System

EHU is one of three charging sources in a typical campervan, alongside solar panels and a DC-DC charger. Here is how EHU fits in:

Before a trip: Plug in at home to start with a 100% battery
On site: Let the mains charger maintain the battery while you use 230V appliances
Between sites: Switch to solar and DC-DC charging
Extended stays: EHU keeps you fully powered without draining the battery

The key point: a well-designed system does not depend on EHU. It is a convenience, not a necessity. If you have adequate solar and a good DC-DC charger, you can skip paid hook-up entirely during summer — saving money and opening up wild camping opportunities.

Plan Your Hook-Up Needs

Our calculator shows how much you rely on EHU based on your solar, battery, and driving habits — so you know whether to book EHU pitches or save the money.

Open Calculator

Safety Considerations

Earth Bonding

Your van's 230V system must be earthed. In a caravan or motorhome, the earth connection comes through the hook-up cable from the site bollard. All exposed metalwork in the 230V system (including the van body if it forms part of the installation) must be bonded to this earth.

RCD Protection

A 30mA RCD is non-negotiable. It protects against electric shock if a fault occurs. Test it monthly by pressing the test button — it should trip instantly. If it does not, replace it immediately.

Cable Condition

Inspect your hook-up cable before each use. Look for cuts, abrasion, cracked insulation, or damaged connectors. A damaged cable in wet grass is a serious electrocution risk. Replace any cable that shows signs of wear.

Water and Electricity

Your shore power inlet must be weatherproof. Ensure the cover closes properly when the cable is connected. Route mains cabling inside the van away from water sources (sinks, windows that might leak). All internal 230V wiring should be enclosed in trunking or conduit.

Frequently Asked Questions

Can I use EHU at home?

Yes. If your van is parked near a 13A domestic socket, you can use a caravan site adapter (CEE to 13A plug, about £15) to connect. The supply is limited to 13A (3kW) from a domestic socket, which is plenty for a battery charger and light use. Ensure the socket is RCD-protected (all modern UK sockets on a ring main should be).

Do I need EHU if I have solar and a DC-DC charger?

Not necessarily. Many UK van lifers go entire summers without using EHU. However, in winter or during extended static stays, EHU is extremely convenient and keeps your battery in optimal condition. It is worth installing the inlet and consumer unit even if you rarely use it.

Is EHU safe in the rain?

Yes, when using proper equipment. CEE connectors are designed for outdoor use and are IP44 rated (protected against splashing water). Your hook-up cable should be laid out straight (not coiled) and kept out of puddles. The RCD in your consumer unit and on the bollard provides backup protection.

How do I know if a campsite has EHU?

Most booking websites and campsite directories indicate whether EHU is available. Look for "electric hook-up," "EHU," or "mains connection" in the facilities list. The Caravan and Motorhome Club and Camping and Caravanning Club guarantee EHU on most pitches.

What is the difference between 10A and 16A hook-up?

The amperage determines how much power you can draw. 10A gives you 2,300W; 16A gives you 3,680W. Most personal use is fine on 10A. You only notice the difference when running high-power appliances like a kettle or heater. The connector is the same blue CEE plug in both cases.

Can I install EHU myself?

You can install the inlet, cable routing, and consumer unit yourself, but 230V wiring should be inspected by a competent person and ideally completed to BS 7671 (the IET Wiring Regulations). If you are not confident with mains wiring, hire a qualified auto-electrician. The consequences of a 230V wiring mistake are severe.