Batteries and banks
Lead acid or LiFePO4, single or in series for a 24V or 48V bank.
Off-grid and home battery
Draw an off-grid diagram with solar and battery
An off-grid installation is about three things: generating with solar, storing in a battery bank and converting to 230V. WireElectric draws that diagram with real equipment and checks cables and protection per connection.
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 draw before you buy
The right cables at high currents
Current, length and cross-section are calculated per connection so you do not find out later that the battery cable is too light.
DC protection in order
A battery bank needs a main fuse that protects the cable and a safe way to isolate. If that is missing the app says so.
230V behind the inverter is correct
Circuits, breakers and RCD belong behind the inverter output; the check evaluates line, neutral and earth separately.
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.
Components for an off-grid system
The library contains the devices that recur in off-grid installations:
- Victron MultiPlus-II, Quattro and Inverter RS
- Victron SmartSolar MPPT (from 75/15 to 250/100)
- Victron Lynx Distributor and Lynx Power In as busbar system
- SmartShunt and Cerbo GX for monitoring
- Battery bank at 12V, 24V or 48V with DC main fuse
- 230V board: breakers and residual current device behind the inverter
From panel to distribution board
- 1
Choose the battery bank
Place the bank (12V, 24V or 48V) with positive and negative busbar and a DC main fuse.
- 2
Connect the solar
One or more SmartSolar MPPTs with their strings; the app keeps the charge side and the battery side apart.
- 3
Convert to 230V
MultiPlus, Quattro or Inverter RS with the output circuits behind it, optionally with a generator or shore power as backup.
- 4
Check and record
Work through the findings, fill in lengths and cross-sections and save the diagram as a PDF.
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 an off-grid diagram with solar and battery
Off-grid currents are high: a 48V bank with a 5 kVA inverter needs heavy cables, a properly chosen DC main fuse and a sensible busbar layout. Drawing first tells you which cross-section and protection you need, and how the 230V side sits behind the inverter.
You can start drawing without an account.
Open WireElectricQuestions about off-grid diagrams
- Can I draw a 48V system?
- Yes. Batteries in series or a 48V bank; the app calculates the net voltage and warns about devices that do not match.
- How heavy must my battery cable be?
- Enter current, length and cross-section on the connection; the check calculates voltage drop and reports whether cross-section and fuse fit.
- Can I draw multiple MPPTs and strings?
- Yes, place several charge controllers with their own strings and see per net what comes together at the bank.
- Can I use the diagram for an application or installer?
- Print it or save it as a PDF. The advice is an aid; manufacturer documentation remains authoritative.
Also useful
- Back to the homepage
- Draw the wiring diagram for your camper
- Draw the wiring diagram for your boat
- Draw an electrical diagram without learning CAD
- Build a 12V wiring diagram that adds up
- Draw the electrical diagram of a caravan
- Solar panel wiring diagram: series or parallel
- Draw a home battery wiring diagram