EHU means electric hook-up: a connection from a campsite electricity supply to your campervan's 230V system. It can power mains appliances and, if you have a suitable mains battery charger, recharge your leisure battery. Shore power and mains hook-up describe the same arrangement.
The pitch's current limit applies to everything running together. A 16A connector does not guarantee a 16A supply: check the campsite's stated allowance before switching on a kettle, heater or battery charger.
Campsite power limits at a glance
For a simple planning estimate, watts = volts × amps. At a nominal 230V:
| Pitch allowance | Approximate total power | Planning implication |
|---|---|---|
| 6A | 1,380W | A 2,000W kettle alone exceeds the allowance. |
| 10A | 2,300W | A 2,000W kettle leaves only about 300W for other loads. |
| 16A | 3,680W | A kettle and heater together can still exceed the allowance. |
These are calculated limits, not a promise that every appliance combination will work. Include the charger, fridge, water heater and anything else running in the background; check equipment input ratings and leave headroom for startup demand.
Worked example: a 1,000W kettle, 500W charger input, 100W fridge and 65W laptop total 1,665W, or about 7.2A at 230V. That exceeds a 6A pitch allowance. A 2,200W kettle and 2,000W heater total 4,200W before the charger is counted, exceeding 16A. These figures illustrate the arithmetic; use your actual appliance labels.
How Shore Power Works in a Campervan
The mains path is campsite supply → hook-up lead → van inlet → protected distribution circuits → sockets and mains charger. The charger then supplies the leisure battery on the DC side.
That distinction matters: a working 230V socket does not prove the battery is charging. Your charger must also be powered, enabled, correctly connected and compatible with the battery. Likewise, plugging into a campsite does not automatically power sockets that are wired only to a separate inverter.
Start with the charging systems guide if you are planning solar, alternator and mains charging together. The electrical calculator helps you compare daily demand and charging assumptions.
What You Need to Install
| Component | What it does | What to check before buying |
|---|---|---|
| External inlet | Receives the hook-up lead | Correct mating connector, mounting instructions, sealing and access |
| Hook-up lead | Connects the vehicle to the pitch | Outdoor suitability, conductor size, connector standard, length and condition |
| Consumer unit and protective devices | Distributes and protects the mains circuits | Correct specification for the installation and equipment |
| Mains battery charger | Converts mains power into controlled battery charging | Battery chemistry, charging limits and manufacturer settings |
| Sockets or fixed appliance circuits | Supply the planned mains loads | Circuit protection, cable routes, isolation and equipment instructions |
| Earthing and bonding | Forms part of the protective system | Design and testing across every source of AC power |
Shore power inlet and cable
UK camping hook-up equipment commonly uses blue 16A CEE connectors. The lead has a plug for the site supply and a female connector that mates with the vehicle inlet. Keep the inlet accessible and route its wiring where it can be protected from abrasion and moisture. Use the inlet manufacturer's dimensions and sealing instructions rather than a generic hole size.
The Caravan and Motorhome Club's hook-up cable guidance describes the specification for touring leads. Choose a purpose-made, compliant lead; don't substitute a household extension reel. Check the campsite's connection arrangements before travelling.
See the shore power inlet guide for the planning decisions around position and access.
Consumer unit, sockets and charger
A consumer unit contains the protective devices for the incoming supply and outgoing circuits. RCD protection and overcurrent protection do different jobs; neither replaces correct earthing, suitable wiring or installation testing. The required device types, ratings and cable sizes depend on the actual design, so a generic component list is not a finished wiring specification.
The consumer unit guide and 230V sockets guide explain the components and layout questions. Keep mains installation and testing with a suitably qualified person familiar with vehicle installations.
For battery charging, start with the mains charger comparison. Match the charging profile to the battery manufacturer's instructions. If you use an IP22, the Victron Blue Smart IP22 setup guide covers that product separately.
Adding Shore Power to an Existing Off-Grid System
Record what is already fitted before ordering parts: battery chemistry and capacity, existing charger models, inverter type, socket layout, earthing arrangement and available space. Identify whether you only want to charge the battery, supply dedicated mains sockets, or supply the same sockets from either shore power or an inverter.
That last option needs particular care. Do not join an inverter's AC output directly to the shore supply. The changeover arrangement and protection must suit the equipment and prevent one source feeding into the other. Read the inverter transfer-switch guide, then have the complete arrangement designed and checked.
Allow access for inspection and maintenance. Spare space in an enclosure can be useful, but adding another circuit later still requires design and testing; an empty slot alone does not make an addition safe.
How to Connect at a Campsite
Follow your vehicle instructions and the site's procedure. The Caravan and Motorhome Club's connection guidance starts with the vehicle's isolating switch off and the cable fully unwound. Connect the vehicle end first, then the site end, following any socket-specific locking instructions. Carry out the prescribed RCD and polarity checks before using the supply.
For disconnection, switch off as instructed and disconnect the supply end before removing the vehicle connector. Inspect the lead and connectors before each use. Keep connections out of standing water and protect the cable from vehicle traffic and sharp edges.
Reversed polarity or a failed check
Stop using the supply if a tester indicates a fault or the RCD does not operate as instructed. Notify the site staff and seek competent help; don't treat an apparently working appliance as evidence of a safe supply. The Club's mains installation guidance says the installation should not be used with reversed polarity.
A basic plug-in tester and the RCD test button do not replace installation inspection and instrument testing. Do not open live equipment, improvise a reversal lead or repeatedly reset a device that trips.
Managing Your Load
List the mains input power of each appliance. A charger described as “30A” normally refers to its DC output, not 30A drawn from the campsite. Use its stated AC input when estimating the pitch load.
Run high-power appliances in sequence when needed: turn the heater down or off before boiling the kettle, and remember automatic loads such as a water heater. If your equipment supports an AC input limit, configure it according to its manual and the available supply.
EHU Costs and Whether You Need It
Compare the total pitch price, any hook-up supplement and any metered electricity charge for your actual booking. A simple budgeting example: a £5 nightly supplement adds £70 over 14 nights. This is an example, not a current campsite tariff.
Solar and alternator charging may cover a trip without hook-up, depending on demand, weather and driving. Mains charging can still be useful for winter, longer stationary stays and pre-trip charging. Decide from your energy plan rather than assuming either that hook-up is essential or that solar makes it unnecessary.
Plan your charging options
Use your appliances and travel plans to compare battery demand, solar and driving recharge in the free electrical calculator.
Frequently Asked Questions
Does EHU charge my leisure battery automatically?
Only if a suitable mains charger is installed, powered and enabled. If mains sockets work but the battery is not gaining charge, check the charger's status and follow the battery charging troubleshooting guide.
Can I use EHU at home?
A suitable home connection can supply a van, but its protection, outdoor equipment and available current need checking. A household plug adaptor does not turn a 13A outlet into a 16A supply. Have the arrangement assessed rather than assuming an indoor socket and extension lead are suitable.
Is EHU safe in the rain?
Use equipment designed for the conditions, assembled and positioned as its manufacturer specifies. A splash-resistance rating does not mean connectors can sit in puddles. Stop using damaged or water-contaminated equipment.
What is the difference between 10A and 16A hook-up?
At nominal 230V, the calculated total allowances are 2,300W and 3,680W. The same style of connector may be used for either. The site's stated current limit determines your allowance.
Can I use an inverter and shore power in the same van?
Yes, with a correctly designed system. Supplying the same sockets requires an appropriate changeover or integrated inverter-charger arrangement; the two AC sources must not be connected together indiscriminately.
Can I install EHU myself?
You can plan the component positions and discuss requirements with an installer. For the mains installation, protection, earthing and testing, use a suitably qualified person with relevant vehicle experience. This guide is not an installation certificate or a statement that a particular design complies with every applicable requirement.
Related
- Campervan charging systems
- Shore power inlet planning
- Consumer units and circuit protection
- 230V sockets in a campervan
- Campervan earth bonding
- Shore power adapters for European trips
- Combining solar, alternator and mains charging
Continue planning
See the campsite tourer wiring example for its complete HTML cable and fuse schedule, assumptions and downloadable PDF.
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Jack Kennedy is a self-builder who has built two vans. He created Roam Wired to simplify conversion planning and share free tools, supported by affiliate links.
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