Let's face it - those large solar panels on your van's roof haven't quite delivered the level of power self-sufficiency you had hoped for. The 1200Ah battery bank you hoped to serve your power needs for the entire week has only encouraged you to bring more home comforts onboard. So, that shore power lead you thought you'd never need again will still be joining you on your trip.
The good news is that you don't have to struggle with your old, long, and bulky lead if you don't want to. Our extensive collection of shore power leads comes in a variety of sizes, including shorter options that can help maximise your limited space.
In this guide, however, we'll primarily focus on the HPM caravan power lead range. These are among the best-selling options in the country, thanks to their excellent performance, high durability, and unmatched reliability wherever you may be travelling across Australia. They all differ only in pricing and total reach, and each features a wide shroud on the female plug, so you can only use them with wide shore inlet sockets.
Why You Need a Genuine Shore Power Lead for Your Adventure Vehicle
When building a shore power system for your adventure vehicle, there's no room for compromise. Both the shore inlet socket and the extension lead must be properly designed to ensure safe and effective performance. This is precisely why we have the Australian electrical regulatory framework in place.
For instance, the regulatory code AS/NZS 3001 (an extension of AS/NZS 3000) covers electrical installations in transportable vehicles/structures and connectable sites such as campsites. One of its key wiring rules specifies that standard supply outlets at campsite hookups should be 15A versions. And as a result, your caravan, campervan, RV, or boat must have a matching 15A shore inlet for compatibility.
To connect the mains supply at a campsite to your vehicle's shore inlet, you'll also need a compatible extension lead. Your shore power lead must be capable of safely carrying 15 amps of 230/240VAC - both along the core and at the connection ends.
Using an improvised power lead - whether a lower-amperage cable or a makeshift plug - can expose you to serious risks. In such cases, these national electrical guidelines won't protect you if something goes wrong. Then, manufacturers may refuse to honour warranties for the damaged devices, and so is the insurer of your adventure vehicle.
Moreover, campsite staff may inspect your shore power lead before allowing you to connect. If they consider it unsafe, they have the right to deny you access to their power supply.
Therefore, having the correct power lead for your camper or boat is just as important as carrying the appropriate charger for your leisure battery. It also means ensuring that the extension lead you purchase meets all compliance requirements.
Which HPM Caravan Power Lead Lengths Are Available?
HPM is one of the oldest and most trusted manufacturers of everyday electrical solutions in Australia. The company offers an extensive catalogue of power points, switches, plugs, connectors, protection devices, powerboards, adaptors, and extension leads for household, workshop, and adventure-vehicle applications.
Within its range of extension leads for adventure vehicles, HPM offers five options you can consider:
- 25m HPM Caravan Extra Heavy-Duty 15A Power Lead
- 20m HPM Caravan Extra Heavy-Duty 15A Power Lead
- 15m HPM Caravan Extra Heavy-Duty 15A Power Lead
- 10m HPM Caravan Extra Heavy-Duty 15A Power Lead
- 8m HPM Caravan Extra Heavy-Duty 15A Power Lead
Length is the only distinguishing feature across these five leads. If you want to be prepared for virtually any campsite, the 25-metre shore power lead is the best choice.
The 25-metre lead allows you to connect the shore power inlet of your van, RV, or boat to a 230/240 VAC outlet up to 82 feet away. It is also useful when the outlet is obstructed and requires you to route the cable along a longer path.
Meanwhile, the 8-metre extension lead is the shortest option in this category. Even so, it still provides about 26 feet of reach from your camper to the 15A power point. If that's too short for your liking, you can opt for the 10-metre, 15-metre, or 20-metre versions.
Other Features of the HPM Caravan Power Leads
Apart from overall length, all other features of these HPM extension leads are identical. This includes build quality, electrical rating, ampacity, and design, as we shall break down below.
Thick, Heavy-Duty Insulation
One of the first things you'll notice with these leads in your hands is their robust construction. They are notably thick, with rugged insulation - hence the "Extra Heavy-Duty" designation.
We have heard some customers complain that the leads are thicker than expected. However, this heavy insulation is intentional, designed to ensure maximum electrical safety under high power loads. It offers high dielectric strength, helping to prevent electrical leakage and associated risks such as electric shock, short circuits, and fire hazards.
Furthermore, the thick insulation protects the core conductors from environmental elements like moisture. It also absorbs mechanical stress - such as bending, crushing, being stepped on, or run over - thereby reducing the risk of damage.
Therefore, when HPM was designing these caravan power leads with such insulation, they did so for your best interest. After all, these cords carry significant electrical loads, and you definitely will be running them on the ground.
What Voltage Does a Caravan Extension Lead Support?
The second reason these HPM leads are great for caravanning, RVing, and boating is their compatibility with campsite hookups across the country. They support a nominal operating voltage of 230-240 VAC @ 50 Hz, which aligns with national electrical standards.
The electrical code AS/NZS 3000 specifies a nominal system voltage of 230 VAC @ 50 Hz across Australia. However, some areas still operate closer to 240 VAC, reflecting the country's earlier standard before the transition to 230 VAC to align with international standards, particularly IEC 60038.
Because HPM extension leads are rated across a 230-240 VAC range, they remain compatible with both new and older supply conditions - including areas like parts of rural Western Australia where 240VAC is still common.
Standard AU/NZ Connectors
As an Australian brand, HPM has created its caravan extension power leads to be compatible with our receptacle configuration. This complies with the national code AS/NZS 3112, which standardises Type I plugs and sockets for household, commercial, and transportable structures and vehicles.
Type I receptacles are these connectors you see having a distinctive three-pin configuration, with two flat pins in an inverted "V" shape and one vertical earth pin.
The AS/NZS 3112 standard further specifies that 15A Type I receptacles must have a wider earth pin than the 10A version. This design prevents users from plugging a 15-amp device into a 10A outlet, which could otherwise lead to overheating, equipment damage, and potential fire hazards.
In this regard, all the HPM leads we've listed feature 15A Type I male and female connectors on either end. The male connector (plug) connects to the 15A outlet at the campsite, while the female connector (socket) plugs into your camper's shore inlet.
How Much Power Can a 15 Amp Extension Lead Carry?
Based on Watt's law, with a maximum voltage of 240VAC and a 15-amp load current, HPM caravan extension leads can carry up to 3600W of power (240 x 15). As such, the inverter charger, battery charger, air conditioner, or any device connected to your shore power socket should not exceed this limit. In fact, your load should maintain a 15-20% safety margin for optimal performance.
If the connected load exceeds the maximum wattage (or 15 amps), the overload safety switch (circuit breaker) in the mains supply will trip. In the event the breaker fails to trip, the excessive power draw may overheat the conductors in the cable, plug, and socket, potentially melting the insulation and starting a fire.
Therefore, when using any of the HPM caravan leads, ensure that the total connected load - whether individual or cumulative - never exceeds 3600W.
Properly Sized Core
Can these leads really carry 15 amps continuously? Like standard wiring cables, a shore extension lead must safely and effectively deliver power to your camper. This is a mandatory requirement under code AS/NZS 3000, which stipulates that cables must be properly sized to carry the maximum load current safely.
HPM caravan extension leads meet this requirement, as they feature a copper core with a cross-sectional area of 1.5 mmΒ². A 1.5 mmΒ² copper wire is usually rated to carry up to 18 amps, so it can safely handle a continuous 15-amp supply without the risk of overheating.
Highly Conductive Copper Conductor
As we've just mentioned, these HPM leads use copper as the core conductor. Copper offers excellent electrical and thermal conductivity, allowing smooth power flow to your caravan, campervan, RV, or boat without overheating. Hence, the reason a 1.5 mmΒ² core is sufficient for this application.
If the conductor were aluminium - which is less conductive than copper - the core would need to be larger, typically around 2.5 mmΒ², to safely support a 15-amp capacity.
It's also worth mentioning that copper has higher tensile strength, ductility, and flexibility than aluminium. As a result, HPM shore leads offer strong mechanical durability, allowing you to bend, route, and coil them for storage without risking damage to the core.
Flashy, Extra-Safe Design
HPM caravan extension leads consist of a long cord with a Type I plug on one end and a socket on the other. The cord comes in a bright orange colour that's not only cute but also highly visible from a distance. This makes it easy to spot when lying on grass, concrete, or dirt.
Per electrical code AS/NZS 3112, the active and neutral pins of the plug are insulated at the base, leaving only the tips conductive. Both the plug and socket also feature clear, heavy-duty moulding.
First, this clear moulding serves its main protective purpose - shielding the cable's connection points from tampering, environmental elements, and mechanical stress such as pulling or twisting. Then, it allows for easier inspection of the terminal connections without needing to cut open the plug or socket. This includes checking whether connections have loosened, overheated, or corroded.
Important Note
HPM innovated these leads for use with modern shore inlet sockets that have a wide opening. If your caravan, RV, campervan, or boat has an older inlet socket with a narrower opening, the female end (socket) of these extension leads - due to its wide shroud - may not fit.
In such cases, you may need to modify the female plug for compatibility with your smaller inlet sockets.
How Much Does a Caravan Power Lead Cost?
When it comes to cost, the price of these HPM leads generally corresponds to their length. For example, the 25-metre version is the most expensive on the list, retailing for around $90. Meanwhile, the 8-metre version is the most affordable option, with a regular price of about $40.
In other words, the shore power lead you choose depends on your desired level of convenience and your budget. The longer the lead, the higher the cost.
At Campervan Builders, we offer all these extension leads with a one-year warranty. You can buy either of them with confidence, knowing we'll support you in case of any issues.
Are HPM Caravan Power Leads Worth Buying?
Yes, HPM caravan extension leads are among the best options available for shore-powering your adventure van, RV, or boat. While they may be slightly more expensive than many generic alternatives on the market, they are proudly made in Australia to withstand tough Australian conditions and comply with Australian safety standards.
Whichever power lead you may choose, it's important to follow proper safety practices for optimal performance. This means only connecting to a 15A socket and avoiding any modification of the male plug to fit a standard 10A household outlet - a risky shortcut many desperate users attempt.
To safely and legally connect your HPM caravan power lead to a 10-amp outlet, you'll need a dedicated 15A to 10A shore power adapter. A good example is the Ampfibian Max 15A to 10A Power Adaptor, though that's a topic for another day.
Frequently Asked Questions
What length caravan power lead should I buy?
HPM offers five lengths: 8m, 10m, 15m, 20m, and 25m. The 8-metre lead provides about 26 feet of reach, while the 25-metre lead reaches a 230/240 VAC outlet up to 82 feet away - the best choice if you want to be prepared for virtually any campsite or an obstructed outlet.
How much power can a 15 amp extension lead carry?
Based on Watt's law, with a maximum voltage of 240VAC and a 15-amp load current, these leads can carry up to 3600W of power (240 x 15). Your total connected load should never exceed 3600W, and ideally should maintain a 15-20% safety margin for optimal performance.
Can I plug a 15A caravan lead into a 10A household outlet?
No - never modify the male plug to fit a standard 10A household outlet, as this is a risky shortcut. To safely and legally connect to a 10-amp outlet, use a dedicated 15A to 10A shore power adapter such as the Ampfibian Max 15A to 10A Power Adaptor.
Will HPM caravan power leads fit older shore inlet sockets?
These leads are designed for modern shore inlet sockets with a wide opening. If your vehicle has an older inlet socket with a narrower opening, the female end's wide shroud may not fit, and you may need to modify the female plug for compatibility.
Ready to hook up to shore power safely? Browse our full range of caravan power leads and order yours with a one-year warranty today.
