Wiring Your Camper: A Step-By-Step Guide

Wiring a camper can be a daunting task, but with the right tools, knowledge, and safety precautions, it is certainly possible to do it yourself. Whether you're dealing with a vintage camper or a modern DIY camper van, there are a few key things you need to know about camper wiring.

First, it's important to understand the different wiring systems in a camper. Typically, there are three types of wiring systems: trailer lights, a 12-volt system, and a 110-volt or 120-volt system. The trailer lights illuminate when you drive, while the 12-volt system powers interior lights, water pumps, and other low-voltage devices. The 110-volt or 120-volt system runs your lighting and outlets when plugged into shore power.

When wiring a camper, it's crucial to use the appropriate tools and materials. This includes wire cutters, crimpers, connectors, stranded wire, fuses, breakers, and a voltage meter. It's also important to wear personal protective equipment (PPE) when working with electricity.

Additionally, understanding the basics of electricity is essential. Electricity is the flow of electrons through a conductor, and it can be thought of as similar to water flowing through a pipe. Voltage is the difference in charge between two points, resistance is the opposition to current flow, and current is the rate at which electrons flow through a conductor.

When wiring a camper, it's important to consider the power sources and loads. Power sources can include solar panels, alternators, and shore power, while loads are the devices that use energy, such as lights, fans, and appliances. To ensure your camper's electrical system functions properly, you need to size your system correctly, taking into account factors such as battery capacity, solar panel wattage, and inverter size.

Finally, when it comes to actually wiring your camper, there are a few key steps to follow. First, create a wiring diagram to plan out the flow of electricity. Then, calculate the amperage and wattage of your loads to determine the size of wires, fuses, and breakers you need. Install the wires, connectors, and fuses according to your diagram, and always make sure to test your work with a voltage meter before turning on the power.

By following these steps and staying safe, you can successfully wire your camper and enjoy your travels with all the comforts of home.

How to wire trailer lights

To wire trailer lights, you'll need to make sure you have the right parts, understand the different types of trailer connectors, and follow some pro tips to ensure a reliable connection.

Parts

You'll need to make sure your vehicle has a standard connector that matches your trailer's connector. You can use adapters to bridge the gap between different connector types. You'll also need a wiring harness, tail lights, and lightbulbs.

Connector Types

The most common connector type is the 4-way flat connector, which is used for small utility trailers, pop-up campers, and boat trailers. The 5-way flat connector is similar but includes an additional pin for auxiliary power or reverse lights and is often used for trailers with hydraulic brakes. The 6-way connector is commonly used for larger trailers and includes two additional pins for electric brakes and battery charging. The 7-way connector is the most versatile and comprehensive, with all the functions of the 6-way connector and a separate pin for a dedicated ground connection. It is commonly used for large RVs, fifth-wheel trailers, heavy-equipment trailers, and livestock trailers.

Pro Tips

• Ensure connectors match before planning to tow.
• Ensure connectors are firmly pressed together.
• Secure the connection to prevent harness damage when towing.
• Conduct a light function test before towing.
• Disconnect and reconnect if something doesn't work.
• If issues persist, check the fuse(s) on the wiring harness and also check the wiring harness on the vehicle and trailer for cut, corroded, or damaged wires.
• If using a taillight converter, check to make sure your taillights are working properly and double-check the connection to the taillights.
• If issues persist, don't forget to check lightbulbs.
• Visually inspect and troubleshoot trailer wiring and lamps.
• Check the power, ground, and fuses if still having issues.
• Use an electrical tester to verify vehicle socket functionality.
• Replace damaged components.
• Keep the connectors covered when not in use.

Wiring

The most important wires are the green (right turn signal), yellow (left turn signal), and brown (running lights). The blue wire is for electric trailer brakes, the red or black wire is for auxiliary power, and the white wire is the ground wire.

How to wire a 12-volt system

A 12-volt system is an essential part of a camper van conversion. This system powers devices directly from the batteries without the need for voltage converters. It is the most power-efficient option, as devices that operate on 12-volt power can run directly from the batteries, eliminating the energy loss that comes with using an inverter.

Step 1: Wiring Multiple Batteries Together

If you are using more than one battery, they should be wired in parallel to increase power capacity without increasing voltage. This involves connecting each battery's positive terminals with red wire and each battery's negative terminals with black wire.

Step 2: Wiring the Batteries to the Bus Bars

Bus bars are power distribution and collection centres that allow you to connect other devices to your batteries. You will need to connect your batteries to the positive and negative bus bars using appropriately-sized wires and components to ensure electrical safety.

Step 3: Wiring the Bus Bar to the 12V Panel

The bus bars will now need to be connected to the 12V fuse panel, which distributes 12V power from the batteries to each 12V device. This step also requires the correct wire size and components to ensure safety.

Step 4: Wiring the 12V Panel to Each Device

In this step, you will connect the fuse panel to each 12V device using 14 AWG wire, which can handle up to 180W of power. This wire can be upgraded to 12 AWG for circuits longer than 20 feet to combat voltage drop. You will also need various components to connect the fuse panel to each device, such as blade fuses and lever nuts.

Step 5: Grounding the 12V System

The final step is to connect the inverter to a designated ground point on the van's chassis, using an appropriately-sized ground wire.

How to wire a 110-volt system

To wire a 110-volt system in a camper, you will need to follow these steps:

• Understand the difference between 110V and 120V: The terms 110V and 120V refer to the same type of Alternating Current (AC) outlet and can be used interchangeably. In practice, the voltage in a house is delivered at 120V, but by the time it reaches the plug, it could be as low as 110V due to transmission losses in the wires.
• Know the basics: The 'hot' wires are black and are connected to the gold screws on the right of the outlet. The 'neutral' wires are white and are connected to the silver screws on the left. The 'ground' wire is green or bare copper and is connected to the green screw on the left.
• Wiring a 120V outlet: When wiring a 120V outlet, connect the incoming and outgoing 'hot' wires (black) to the two gold screws on the right. Then, connect the incoming and outgoing 'neutral' wires (white) to the two silver screws on the left. Finally, connect the 'ground' wire (green or bare copper) to the green screw on the left.
• Wiring multiple 120V outlets on the same circuit: This can be done by wiring the outlets in parallel. Connect the incoming 'hot' wire (black) to one of the 'hot' screws (gold screw on the right), and the outgoing 'hot' wire (black) to the other 'hot' screw. Do the same for the 'neutral' wires (white) by connecting them to the 'neutral' screws (silver screw on the left). For the 'ground' wire, connect the incoming, outgoing, and short jumper wire with a lever nut and then connect the jumper wire to the ground screw (green).
• Number of outlets on the same circuit: There is no limit to the number of outlets that can be on a single circuit. What matters is the total wattage of the devices plugged into all the outlets on that circuit. If the total wattage exceeds the circuit capacity, it will overload the circuit and trip the breaker.
• Wiring a 110/120V light fixture: If your light fixture has three wires (black, white, and green), it is a 120V light and should have black, white, and green wires run to it. If it has only one (hot) or two (hot and neutral) wires, it is a 12V light and should have red and black wires run to it.
• Choosing the right components: Use a converter to change 120V AC power to 12V DC power. A converter/charger also continuously charges the camper's battery, allowing for off-grid camping. Use an inverter to change 12V DC power to 120V AC power.
• Battery selection: Choose a 12V deep cycle marine battery, preferably an Absorbent Glass Mat (AGM) battery. AGM batteries are safer, charge faster, and have a longer lifespan than other types of batteries.
• Fuse block and bus bar: A fuse block allows one source of power to come in and multiple sources to go out through fuses. A bus bar is similar but does not have the added safety layer of fuses.
• Shore power inlet: Depending on your power requirements, you can choose between a 30 Amp or 50 Amp shore power inlet. A 30 Amp inlet is usually sufficient for most camper appliances, while a 50 Amp inlet is needed for more power-hungry devices.
• Wiring diagram: Power comes in from the shore and runs to the battery, charging it and then to the inverter, powering it. Power also runs from the 12V battery to the 12V DC electrical system.
• Grounding: Ensure proper grounding of your camper by connecting to both the chassis (camper trailer) and bare aluminum walls. Use an 8AWG 15' red and black cable, #10 screw heat shrink ring connectors, a machine screw with a matching hex nut, and anti-oxidant joint compound to improve conductivity.
• Wiring 110V outlets: All positive, negative, and ground 12AWG wires for your 110V appliances, lights, etc., should be hard-wired into a grounded electrical plug and plugged into the inverter directly.

How to wire a 120-volt outlet

To wire a 120-volt outlet, you need three wires: green or bare copper for the ground, white for neutral, and usually black or red for the hot (live) wire. In a home setting, you would typically use Romex wire, which can be purchased at a hardware store. Romex wire is solid and usually comes in 14/2, meaning the hot/neutral wire gauge is 14 AWG and includes a bare ground. However, stranded wire is easier to use in an industrial setting, such as a farm.

Before beginning any wiring work, it is important to turn off the power at the breaker panel to avoid electrical shocks. Use electrical strippers to strip the insulation from the wire at about 1/2" from the end, exposing the bare copper wire. If using stranded wire, it is best to install spade connectors onto the bare wire. Slide the connector onto the wire and use the crimp slots to tightly secure the connector. Repeat this process for each wire.

Loosen the green ground screw and attach the green spade to the green screw, tightening it with a screwdriver. If using solid copper wire, create a small loop in the wire and wrap it around the screw's threads before tightening. Next, loosen the top silver screw and attach the neutral wire to one of the silver screws. On a standard 110/120 volt outlet, the neutral wire attaches to the long prong hole. Tighten the screw with a screwdriver. Again, if using solid copper wire, create a small loop and wrap it around the screw's threads.

If this outlet is the last in a series, only the first set of screws will be used. If continuing to another outlet, the other set of screws will be used for the wires leading to the next outlet. Loosen a gold screw and attach the hot wire to the gold screw (the short prong side), tightening with a screwdriver. As before, if using solid copper wire, create a small loop and wrap it around the screw's threads.

Now, attach the outlet to the box by screwing in the two attachment screws that come with the outlet. Ensure that the bare ground wire does not touch any of the hot screws, as this will short the power and trip the breaker. Attach the outlet cover, and you are ready to turn on the breaker and test the outlet.

When wiring a camper, it is important to understand the difference between 120 Volt AC power and "low voltage" 12 Volt DC power. 120 Volt AC power typically runs more luxurious items, such as air conditioning units and water heaters, while 12 Volt DC power is used for necessities like lights, smoke detectors, and water pumps. To save energy, it is recommended to split USB and standard outlets, as converting and inverting power between them wastes energy.

A converter converts 120V AC power to 12V DC power, while an inverter performs the opposite function. A converter/charger also continuously charges the camper's battery, allowing for boondocking or off-grid camping. A fuse block acts as a breaker panel for the camper, providing an added layer of safety by allowing a fuse to pop and protect the system in case of an overload.

When wiring a camper, it is crucial to ensure proper grounding to the chassis and bare aluminum walls. This can be done by cleaning the mounting areas with a grinder or Dremel, creating a small hole for a machine screw, and using heat shrink ring connectors and anti-oxidant joint compound to improve conductivity.

How to wire multiple 120-volt outlets on the same circuit

Wiring multiple 120-volt outlets on the same circuit is simple. It involves connecting the outlets in parallel. Here is a step-by-step guide:

• Connect the incoming 'hot' wire (black) to one of the 'hot' screws (the gold screw on the right).
• Connect the outgoing 'hot' wire (black) to the other 'hot' screw (also the gold screw on the right).
• Connect the incoming 'neutral' wire (white) to one of the 'neutral' screws (the silver screw on the left).
• Connect the outgoing 'neutral' wire (white) to the other 'neutral' screw (also the silver screw on the left).
• Connect the incoming, outgoing, and short jumper of ground wire with a lever nut and connect the jumper wire to the ground screw (green) on the bottom left.

It is important to note that stranded wire is recommended for mobile applications. Ring or spade terminals can be used to connect wires to screws.

Frequently asked questions