Batteries and banks
Lead acid or LiFePO4, single or in series for a 24V or 48V bank.
Caravan and trailer
Draw the electrical diagram of a caravan
A caravan usually has a small 12V system next to a 230V section fed by shore power. WireElectric lets you draw that combination with real devices, including the link to the tow car.
Drawing and checking is free and works without an account.
- Free drawing, no account
- Victron components with real terminals
- Checks on cables, fuses and voltage
What can you draw?
Every part comes from the component library with real ports, voltages and currents.
Solar panels
Panels in series or parallel to a charge controller at the right voltage.
MPPT charge controller
Charge controllers between solar and battery, including Victron models.
DC-DC charger
Charging from the alternator or starter battery over a DC-DC charger.
Inverter
From 12V or 24V to 230V for your onboard appliances.
Shore power and charger
Mains connection with battery charger, RCD and circuit groups.
12V and 24V loads
Lighting, pump, fridge and other loads with a fuse per circuit.
230V circuits
Sockets and fixed connections behind your inverter or shore power.
Why a caravan diagram helps
Shore power next to 12V
Shore power through the CEE inlet, a breaker and earth leakage device, and the mains charger keeping the battery topped up: all in one drawing.
Long runs, small conductors
From battery to rear wall is easily four or five metres. The check calculates the voltage drop over that length.
Expand without surprises
Adding a panel or inverter? You see straight away whether the existing cables and fuses can carry the extra current.
Automatic checks while you draw
WireElectric calculates along as you connect parts and reports what does not add up.
Wire size
The required cross-section follows from current, length and allowed voltage drop.
Fuses
A fuse that does not match the cable or the device is flagged.
Voltage drop
Per cable you see the loss in volts and percent.
Connections
Ports that do not match in voltage or type raise a warning.
What belongs in a caravan
The library covers the parts you find in a caravan or folding trailer:
- 12V battery (AGM or LiFePO4) with main fuse and battery switch
- Mains charger or inverter/charger for shore power
- Solar panel with MPPT or PWM charge controller
- CEE shore power inlet, breaker and earth leakage device
- Fuse holder, distribution block and negative busbar
- Loads: lighting, water pump, fridge, fan and USB outlets
From battery to complete drawing
- 1
Battery and protection
Place the battery with a main fuse and battery switch, plus the negative busbar as the central ground point.
- 2
Charging
Mains charger on the shore power circuit, optionally a solar panel with controller and a charge line from the tow car.
- 3
The 230V section
CEE inlet, breaker and earth leakage device, sockets and fixed loads such as the water heater.
- 4
12V loads
Lighting, water pump, fridge and fan behind their own fuse, with the cable lengths filled in.
Example wiring diagrams for campervan, boat and off-grid
Calculate it yourself
Every calculator answers one question about your installation. WireElectric then runs the same calculations for every connection in your complete diagram.
Wire gauge calculator
Find the cross-section that suits your 12V or 24V system, based on current, length and voltage drop.
View →Fuse size calculator
Find a suitable fuse for your circuit, including a check on whether the cable can carry it.
View →Voltage drop calculator
Check how much voltage you lose over a cable and what reaches your load.
View →Battery capacity calculator
Work out how much battery capacity in Ah you need for your daily use and autonomy.
View →Battery runtime
Calculate how long a battery can power a load, including the usable share and inverter losses.
View →Watts ↔ Amps
Convert power straight to current at 12V, 24V, 48V or 230V.
View →Solar panel calculator
Work out indicatively how many Wp of solar panels your daily consumption needs.
View →Draw the electrical diagram of a caravan
A caravan looks simple — a battery, some lights, a fridge — until you add solar, an inverter or a second battery. Then the same questions appear as in a camper van: which cable, which fuse, and how do I keep 12V and 230V properly separated? Drawing the diagram first tells you what to buy before you start cutting into panels, and gives you something to show an insurer or inspector.
You can start drawing without an account.
Open WireElectricQuestions about caravan electrics
- Does a caravan need an earth leakage device?
- The 230V section behind the shore power inlet should be protected by a breaker and an earth leakage device, with the earth carried through. The check warns when the earth goes nowhere.
- Can I charge from the tow car?
- You can through the 13-pin connector, but a DC-DC charger is often needed to fully charge the battery. You can draw and compare both options.
- Which conductor size for an inverter in a caravan?
- That depends on the power and the run length. Enter the current and the cable length and the check tells you whether the size is sufficient and how much voltage you lose.
- Is this the same as a camper diagram?
- The parts largely overlap; a caravan simply has no alternator on board. There is a separate page for campers and van conversions that includes alternator charging.
Also useful
- Back to the homepage
- Draw the wiring diagram for your camper
- Draw the wiring diagram for your boat
- Draw an off-grid diagram with solar and battery
- Draw an electrical diagram without learning CAD
- Build a 12V wiring diagram that adds up
- Solar panel wiring diagram: series or parallel
- Draw a home battery wiring diagram