Batteries and banks
Lead acid or LiFePO4, single or in series for a 24V or 48V bank.
Home battery storage
Draw a home battery wiring diagram
A home battery is a small off-grid system: a 48V bank, an inverter/charger, usually solar and a distribution to the circuits you want to back up. WireElectric draws it and checks the cabling and protection.
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 it first
High currents on the bank
The check converts the inverter power back to battery current and compares it with the conductor size and fuse you chose.
Protection in the right place
Every branch from the bank should be protected at the source. A missing main fuse is a finding, not an assumption.
Solar, grid and battery together
Solar through a charge controller, the grid through the inverter/charger and the battery as a buffer sit in one drawing.
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.
Parts of a home battery system
For home storage you use, among others:
- 48V bank of LiFePO4 modules with busbars
- Inverter/charger with AC input and AC output
- MPPT charge controller with panels in series
- Main fuse, fuse holders and a battery switch
- Shunt or battery monitor for charge and consumption
- 230V distribution with breakers and earth leakage protection
Building the diagram
- 1
Choose the bank
Set the voltage and capacity — usually 48V — and place the modules with busbars and a main fuse.
- 2
Inverter/charger
Connect the DC side with the right conductor size and protection and run the AC side to the distribution board.
- 3
Add solar
Panels in strings to an MPPT charge controller, with a fuse on the battery side.
- 4
Circuits and checks
Run the circuits you want to back up to the inverter output and work through the findings.
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 a home battery wiring diagram
Home storage carries higher currents than people expect: a 5 kVA inverter at 48 volts pulls well over a hundred amps from the bank. Conductor size, fuse rating and the position of the main switch then decide whether the system is safe. Drawing the diagram first tells you which cables, fuse holders and busbars to buy, and gives you something concrete to review with your installer.
You can start drawing without an account.
Open WireElectricQuestions about home battery diagrams
- Which cable between battery and inverter?
- Use the maximum DC current of the inverter, not the average. Enter that current and the cable length and the check tells you whether the size is sufficient and how much voltage you lose.
- Can I install this myself?
- Many people build the DC side themselves, but connecting to the house installation is work for a qualified installer and subject to local regulations. The diagram is a tool, not an approval.
- Can I put modules in parallel?
- Yes. Parallel modules are treated as one bank as long as the voltage matches; series and parallel wiring are judged separately so you get no false polarity warnings.
- How is this different from off-grid?
- Technically very little: a home battery sits next to the grid, an off-grid system stands alone. There is a separate off-grid page covering generators and larger banks.
Also useful
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