This is the third part of our DIY Van Electrical Guide trilogy:
Made with in our van.
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Van Electrical Calculator
- Size your battery bank, solar, alternator, shore & inverter automagically or manually.
- Hover / tap any underlined wordUseful Tooltip! to reveal a useful tooltip.
- Start with our Electrical System Guide if you're new to this!
12V DC
SUMMER |
WINTER |
|||||
---|---|---|---|---|---|---|
LOADName of the appliance. | CUR (A)AVERAGE CURRENT (in amps) drawn during operation. Find this info on Google, product's website, owner's manual, technical sheet. |
HRS / DAY (h)How many HOURS per day this appliance is in operation. It's a guesstimate. |
DAILY USAGE (Ah)CURRENT x HOURS |
CUR (A)AVERAGE CURRENT (in amps) drawn during operation. Find this info on Google, product's website, owner's manual, technical sheet. |
HRS / DAY (h)How many HOURS per day this appliance is in operation. It's a guesstimate. |
DAILY USAGE (Ah)CURRENT x HOURS |
TOTAL |
120V AC
SUMMER |
WINTER |
|||||||
---|---|---|---|---|---|---|---|---|
LOADName of the appliance. | PWR (W)MAX POWER (in watts) of the load. Find this info on Google, product's website, owner's manual, technical sheet. |
HRS / DAY (h)How many HOURS per day this appliance is in operation. It's a guesstimate. |
DAILY USAGE (Ah)[(POWER/12) x HOURS] / 0.85 |
INVThis column is used to size the inverter. Check all the appliances that you plan on using simultaneously. Note that the biggest load is automatically selected by the calculator. | PWR (W)MAX POWER (in watts) of the load. Find this info on Google, product's website, owner's manual, technical sheet. |
HRS / DAY (h)How many HOURS per day this appliance is in operation. It's a guesstimate. |
DAILY USAGE (Ah)[(POWER/12) x HOURS] / 0.85 |
INVThis column is used to size the inverter. Check all the appliances that you plan on using simultaneously. Note that the biggest load is automatically selected by the calculator. |
TOTAL |
Battery Type
Your Type
WINTER columns added. The calculator compares summer VS winter and works with the "worst" case scenario (most power usage).
Alternator
1- Size Your Main Components
Use the calculator above
Daily Energy Usage
? Ah
Battery Bank
? Ah
Solar Panels
? W
Solar Charger
?|?
Alternator Charge
? A
Shore Charger
? A
INVERTER
? W
Manual Mode Enabled.
Bold options = automagic values.
- DIAGNOSIS
- Does not compute. I need at least one load (12V DC or 120V AC) to size your system. Beep boop!
- Battery Bank: You need over 600Ah. Consider switching to Lithium instead.
- Battery Bank: You need over 600Ah and that's over my capacity. Beep Boop!
- Battery Bank: You need over 600Ah and that's over my capacity. Beep Boop!
- Battery Bank: Consider upgrading to a larger battery bank or adjusting your needs in 12V DC & 120V AC tables.
- SOLAR: The selected solar delivers too much current for this battery bank. Choose a smaller solar or upgrade the battery bank.
- Alternator: The selected charger delivers too much current for this battery bank. Choose a smaller charger or upgrade the battery bank.
- Alternator: The selected charger is too big for your vehicle's alternator ("small" VS "regular" VS "Heavy-Duty/Dual"). Choose a smaller alternator charger.
- Shore: The selected charger delivers too much current for your battery bank. Choose a smaller charger or upgrade the battery bank.
- Inverter: You need over 3000W and the wiring diagram doesn't support that. Beep Boop! Make sure to only check loads that'll run simultaneously under "inv" column in "120V ac" table.
- Inverter: Consider choosing a smaller inverter or upgrading your battery bank. Your autonomy is very short with the actual selections.
- Inverter: The selected inverter draw too much current for this battery bank. choose a smaller inverter or upgrade the battery bank.
- Inverter: Consider upgrading to a larger inverter or adjusting your needs in the 120V AC table.
- Heads up! We had to adjust the battery bank, because we found no equivalent following your new selection.
- SHORE CHARGER: not needed with inverter/charger.
2- Size Your Wires, Fuses & Breakers
+ Wire Lengths & Terminals Calculator
Appropriate wire gauge (AWG) varies with length & load and therefore is unique to each installation. Our wiring diagram automatically sizes the wires gauge, fuses & breakers to ensure that your own system is safe and performs as it should. Bonus: it also calculates all the wires lengths & terminals that you'll need by type/gauge, which will make STEP 3 (customize your items list) super easy to complete. No other diagram does this!
- With the inputs you entered, we recommend downloading the HIGH-POWER wiring diagram.
3- Customize Your Items list
Fill these tables per your wiring diagram:
WIRES LENGTH (FT)
AWG | 4/0 | 3/0 | 2/0 | 1/0 | 1 | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
RED | |||||||||||||
BLACK | |||||||||||||
DUPLEX |
TERMINALS QUANTITY
AWG | 4/0 | 3/0 | 2/0 | 1/0 | 1 | 2 | 4 | 6 | 8 | 10/12 | 14/16 |
---|---|---|---|---|---|---|---|---|---|---|---|
#8 | |||||||||||
#10 | |||||||||||
1/4 | |||||||||||
5/16 | |||||||||||
3/8 |
Cost EstimateIncludes everything on your Items List, except the 12V & 120V loads (appliances) and Tools. Prices on Amazon change frequently, so our estimate is subject to change.
$X,XXX USD
Items List
The list below defines your entire electrical system. Click on "ADD ITEMS TO AMAZON CART" section-by-section; make sure that all the items are valid (links to Amazon products sometime change, please let us know if that's the case!) and make sure all items are in stock at the moment.
Main
# | Item | Description | Quantity | View on Amazon |
1 | Terminal Fuse Block with Fuse 250A | Blue Sea (Catastrophic Fail Safe. Connects directly to battery post.) | 1 | View |
2 | System Switch | Blue Sea (Main System Switch) | 1 | View |
3 | Bus Bar (250A, 4 studs) | Blue Sea | 2 | View |
4 | Cover for Bus Bar (for 250A 4 studs) | Protect the Bus Bar | 2 | View |
5 | 40A Breaker/Switch, Surface Mount | Between Fuse Block and Bus Bar | 1 | View |
6 | Fuse Block (12 circuits) | Blue Sea (12V Distribution Panel) | 1 | View |
7 | Fuses Kit | Assorted Fuses (2A 3A 5A 7.5A 10A 15A 20A 25A 30A 35A) | 1 | View |
8 | Battery Monitor | Victron BMV-712 with BlueTooth | 1 | View |
Main
# | Item | Description | Quantity | View on Amazon |
1 | Class T Fuse, 300A | Blue Sea (Catastrophic Fail Safe) | 1 | View |
2 | Class T Fuse Block | Blue Sea (Holds the Class T Fuse) | 1 | View |
3 | System Switch | Blue Sea (Main System Switch) | 1 | View |
4 | Bus Bar (600A, 4 studs) | Blue Sea | 2 | View |
5 | Cover for Bus Bar (for 600A 4 studs) | Protect the Bus Bar | 2 | View |
6 | 40A Breaker/Switch, Surface Mount | Between Fuse Block and Bus Bar | 1 | View |
7 | Fuse Block (12 circuits) | Blue Sea (12V Distribution Panel) | 1 | View |
8 | Fuses Kit | Assorted Fuses (2A 3A 5A 7.5A 10A 15A 20A 25A 30A 35A) | 1 | View |
9 | Battery Monitor | Victron BMV-712 with BlueTooth | 1 | View |
Main
# | Item | Description | Quantity | View on Amazon |
1 | Class T Fuse, 400A | Blue Sea (Catastrophic Fail Safe) | 1 | View |
2 | Class T Fuse Block | Blue Sea (Holds the Class T Fuse) | 1 | View |
3 | System Switch | Blue Sea (Main System Switch) | 1 | View |
4 | Bus Bar (600A, 4 studs) | Blue Sea | 2 | View |
5 | Cover for Bus Bar (for 600A 4 studs) | Protect the Bus Bar | 2 | View |
6 | 40A Breaker/Switch, Surface Mount | Between Fuse Block and Bus Bar | 1 | View |
7 | Fuse Block (12 circuits) | Blue Sea (12V Distribution Panel) | 1 | View |
8 | Fuses Kit | Assorted Fuses (2A 3A 5A 7.5A 10A 15A 20A 25A 30A 35A) | 1 | View |
9 | Battery Monitor | Victron BMV-712 with BlueTooth | 1 | View |
Battery
Nothing to show here. You need to enter some 12V and/or 120V loads, or choose a battery bank if you are in manual mode.
Battery
# | Item | Description | Quantity | View on Amazon |
1 | AGM 100 Ah | Renogy AGM 100 Ah 12V | 1 | View |
Battery
# | Item | Description | Quantity | View Link |
1 | AGM 200 Ah | Renogy AGM 200 Ah 12V | 1 | View |
Battery
Battery
Battery
Battery
# | Item | Description | Quantity | View on Amazon |
1 | LiFePO4 100 Ah | Battle Born LiFePO4 100 Ah 12V | 1 | View |
Battery
Battery
Battery
Battery
Battery
# | Item | Description | Quantity | View on Amazon |
1 | LiFePO4 100 Ah | Renogy LiFePO4 100 Ah 12V | 1 | View |
Battery
# | Item | Description | Quantity | View on Amazon |
1 | LiFePO4 170 Ah | Renogy LiFePO4 170 Ah 12V | 1 | View |
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Battery
Solar
Nothing to show here. You can add solar charging later if you change your mind, as our wiring diagram allows for future expansion!
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 100W Solar | Renogy 100W Mono Panel | 1 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 25A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Victron 75|15 SmartSolar MPPT | 1 | View |
6 | 25A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 175W Solar | NewPowa 175W Mono Panel | 1 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 25A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Victron 75|15 SmartSolar MPPT | 1 | View |
6 | 25A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 200W Solar | Renogy 100W Mono Panel | 2 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 25A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Victron 75|15 SmartSolar MPPT | 1 | View |
6 | 25A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 300W Solar | Renogy 100W Mono Panel | 3 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 40A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Victron 100|30 SmartSolar MPPT | 1 | View |
6 | 40A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 350W Solar | NewPowa 175W Mono Panel | 2 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 40A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Victron 100|30 SmartSolar MPPT | 1 | View |
6 | 40A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 525W Solar | NewPowa 175W Mono Panel | 3 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 60A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Victron 100|50 SmartSolar MPPT | 1 | View |
6 | 60A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 700W Solar | NewPowa 175W Mono Panel | 4 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 60A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Victron 100|50 SmartSolar MPPT | 1 | View |
6 | 60A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 100W Solar | Renogy 100W Mono Panel | 1 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 25A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Renogy Rover LI 20A MPPT | 1 | View |
6 | 25A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 175W Solar | NewPowa 175W Mono Panel | 1 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 25A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Renogy Rover LI 20A MPPT | 1 | View |
6 | 25A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 200W Solar | Renogy 100W Mono Panel | 2 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 25A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Renogy Rover LI 20A MPPT | 1 | View |
6 | 25A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 300W Solar | Renogy 100W Mono Panel | 3 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 40A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Renogy Rover LI 30A MPPT | 1 | View |
6 | 40A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 350W Solar | NewPowa 175W Mono Panel | 2 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 40A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Renogy Rover LI 30A MPPT | 1 | View |
6 | 40A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 525W Solar | NewPowa 175W Mono Panel | 3 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 70A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Renogy Rover LI 60A MPPT | 1 | View |
6 | 70A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Solar
# | Item | Description | Quantity | View on Amazon |
1 | 700W Solar | NewPowa 175W Mono Panel | 4 | View |
2 | Extension Cables, 8 AWG, 15 ft Red + 15 ft Black | With MC4 Connectors | 1 | View |
3 | Double Cable Entry Gland | For 8 AWG or 10 AWG Cable | 1 | View |
4 | 70A Breaker/Switch, Surface Mount | Between Panels and MPPT Charger | 1 | View |
5 | MPPT Solar Charger | Renogy Rover LI 60A MPPT | 1 | View |
6 | 70A Breaker/Switch, Surface Mount | Between MPPT Charger & Battery | 1 | View |
Alternator
Nothing to show here. You can add alternator charging later if you change your mind, as our wiring diagram allows for future expansion!
Alternator
Alternator
Alternator
*Item #1 (BBW12120) is currently not available on Amazon, so you'll have to buy it separately on eBay.
Shore
Nothing to show here. You can add shore charging later if you change your mind, as our wiring diagram allows for future expansion!
Shore
Shore
Shore
Inverter
Nothing to show here. You can add an inverter later if you change your mind, as our wiring diagram allows for future expansion!
Inverter
Optional Items:
Inverter
Optional Items:
Inverter
Optional Items:
Inverter
Optional Items:
Inverter
Optional Items:
Inverter
Optional Items:
Inverter
Optional Items:
Inverter
# | Item | Description | Quantity | View on Amazon |
1 | 2000W Inverter | Renogy 2000W Pure Sine | 1 | View |
2 | Remote Control for Inverter | Included |
Optional Items:
Inverter/Charger
# | Item | Description | Quantity | View on Amazon |
1 | 2000W Inverter/Charger | Victron Multiplus Compact 12|2000|80 | 1 | View |
2 | Remote Control for Inverter | Victron Digital Multi Control 200/200A GX | 1 | View |
3 | Class T Fuse, 300A | Blue Sea (To protect inverter’s cable) | 1 | View |
4 | Class T Fuse Block | Blue Sea (Holds the Class T Fuse) | 1 | View |
5 | 30A Shore Inlet | Furrion 30A Marine Power Smart Inlet | 1 | View |
6 | 30A AC Main | Breaker Between Power Inlet and Inverter/Charger | 1 | View |
7 | 120V AC Distribution Panel (4 Positions*) | Blue Sea Panel: AC Main + 4 Positions* | 1 | View |
8 | 10/3 AWG Triplex AC Marine Wire | Between power inlet & inverter/charger | 1 | View |
9 | 6/3 AWG Triplex AC Marine Wire | Between inverter/charger & AC distribution panel | 1 | View |
10 | 120V AC GFCI Outlet | GFCI | 1 | View |
11 | 14/3 AWG Triplex AC Marine Wire | To wire load that requires 15A or 10A breaker | 1 | View |
Optional Items:
# | Optional Item | Description | View on Amazon |
1 | 50A Breaker (Double-Pole) | To upgrade 120V AC distribution panel to 50A instead of 30A | View |
2 | 20A Breaker | For load that requires 20A breaker (e.g. A/C) | View |
3 | 10A Breaker | For load that requires 10A breaker | View |
4 | 120V AC Distribution Panel (6 Positions*) | *6 Positions panel is sometimes cheaper, check it! | View |
5 | 12/3 AWG Triplex AC Marine Wire | To wire load that requires 20A breaker (e.g. A/C) | View |
Inverter/Charger
# | Item | Description | Quantity | View on Amazon |
1 | 2000W Inverter/Charger | Victron Multiplus Compact 12|2000|80 | 1 | View |
2 | Remote Control for Inverter | Victron Digital Multi Control 200/200A GX | 1 | View |
3 | Class T Fuse, 300A | Blue Sea (To protect inverter’s cable) | 1 | View |
4 | Class T Fuse Block | Blue Sea (Holds the Class T Fuse) | 1 | View |
5 | 30A Shore Inlet | Furrion 30A Marine Power Smart Inlet | 1 | View |
6 | 30A AC Main | Breaker Between Power Inlet and Inverter/Charger | 1 | View |
7 | 120V AC Distribution Panel (4 Positions*) | Blue Sea Panel: AC Main + 4 Positions* | 1 | View |
8 | 10/3 AWG Triplex AC Marine Wire | Between power inlet & inverter/charger | 1 | View |
9 | 6/3 AWG Triplex AC Marine Wire | Between inverter/charger & AC distribution panel | 1 | View |
10 | 120V AC GFCI Outlet | GFCI | 1 | View |
11 | 14/3 AWG Triplex AC Marine Wire | To wire load that requires 15A or 10A breaker | 1 | View |
Optional Items:
# | Optional Item | Description | View on Amazon |
1 | 50A Breaker (Double-Pole) | To upgrade 120V AC distribution panel to 50A instead of 30A | View |
2 | 20A Breaker | For load that requires 20A breaker (e.g. A/C) | View |
3 | 10A Breaker | For load that requires 10A breaker | View |
4 | 120V AC Distribution Panel (6 Positions*) | *6 Positions panel is sometimes cheaper, check it! | View |
5 | 12/3 AWG Triplex AC Marine Wire | To wire load that requires 20A breaker (e.g. A/C) | View |
Inverter/Charger
# | Item | Description | Quantity | View on Amazon |
1 | 3000W Inverter/Charger | Victron Multiplus 12|3000|120 | 1 | View |
2 | Remote Control for Inverter | Victron Digital Multi Control 200/200A GX | 1 | View |
3 | Class T Fuse, 400A | Blue Sea (To protect inverter’s cable) | 1 | View |
4 | Class T Fuse Block | Blue Sea (Holds the Class T Fuse) | 1 | View |
5 | 30A Shore Inlet | Furrion 30A Marine Power Smart Inlet | 1 | View |
6 | 30A AC Main | Breaker Between Power Inlet and Inverter/Charger | 1 | View |
7 | 120V AC Distribution Panel (4 Positions*) | Blue Sea Panel: AC Main + 4 Positions* | 1 | View |
8 | 10/3 AWG Triplex AC Marine Wire | Between power inlet & inverter/charger | 1 | View |
9 | 6/3 AWG Triplex AC Marine Wire | Between inverter/charger & AC distribution panel | 1 | View |
10 | 120V AC Wall Outlet | GFCI | 1 | View |
11 | 14/3 AWG Triplex AC Marine Wire | To wire load that requires 15A or 10A breaker | 1 | View |
Optional Items:
# | Optional Item | Description | View on Amazon |
1 | 50A Breaker (Double-Pole) | To upgrade 120V AC distribution panel to 50A instead of 30A | View |
2 | 20A Breaker | For load that requires 20A breaker (e.g. A/C) | View |
3 | 10A Breaker | For load that requires 10A breaker | View |
4 | 120V AC Distribution Panel (6 Positions*) | *6 Positions panel is sometimes cheaper, check it! | View |
5 | 12/3 AWG Triplex AC Marine Wire | To wire load that requires 20A breaker (e.g. A/C) | View |
Inverter/Charger
# | Item | Description | Quantity | View on Amazon |
1 | 3000W Inverter/Charger | Victron Multiplus 12|3000|120 | 1 | View |
2 | Remote Control for Inverter | Victron Digital Multi Control 200/200A GX | 1 | View |
3 | Class T Fuse, 400A | Blue Sea (To protect inverter’s cable) | 1 | View |
4 | Class T Fuse Block | Blue Sea (Holds the Class T Fuse) | 1 | View |
5 | 30A Shore Inlet | Furrion 30A Marine Power Smart Inlet | 1 | View |
6 | 30A AC Main | Breaker Between Power Inlet and Inverter/Charger | 1 | View |
7 | 120V AC Distribution Panel (4 Positions*) | Blue Sea Panel: AC Main + 4 Positions* | 1 | View |
8 | 10/3 AWG Triplex AC Marine Wire | Between power inlet & inverter/charger | 1 | View |
9 | 6/3 AWG Triplex AC Marine Wire | Between inverter/charger & AC distribution panel | 1 | View |
10 | 120V AC Wall Outlet | GFCI | 1 | View |
11 | 14/3 AWG Triplex AC Marine Wire | To wire load that requires 15A or 10A breaker | 1 | View |
Optional Items:
# | Optional Item | Description | View on Amazon |
1 | 50A Breaker (Double-Pole) | To upgrade 120V AC distribution panel to 50A instead of 30A | View |
2 | 20A Breaker | For load that requires 20A breaker (e.g. A/C) | View |
3 | 10A Breaker | For load that requires 10A breaker | View |
4 | 120V AC Distribution Panel (6 Positions*) | *6 Positions panel is sometimes cheaper, check it! | View |
5 | 12/3 AWG Triplex AC Marine Wire | To wire load that requires 20A breaker (e.g. A/C) | View |
Wires
Nothing to show here. You need to fill the “Wires” table in the calculator above.
Terminals
Nothing to show here. You need to fill the “Terminals” table in the calculator above.
Hardware
# | Item | Description | Quantity | View on Amazon |
1 | Heat Shrink Butt Connector, Ancor Marine | To connect to Loads (75 Pack Kit) | 1 | View |
2 | Heat Shrink Disconnect, 10-12 AWG Cable, 1/4″ Tab, Female | To connect to certain loads (i.e. 12V Sockets) , to make “removable” connections (i.e. Fridge, LEDs) and to connect cable of different gauge together (i.e. LED Dimmer) (25 Pack) | 1 | View |
3 | Heat Shrink Disconnect, 10-12 AWG Cable, 1/4″ Tab, Male | 1 | View | |
4 | Heat Shrink Disconnect, 14-16 AWG Cable, 1/4″ Tab, Female | 1 | View | |
5 | Heat Shrink Disconnect, 14-16 AWG Cable, 1/4″ Tab, Male | 1 | View | |
6 | Heat Shrink Disconnect, 18-22 AWG Cable, 1/4″ Tab, Male | 1 | View | |
7 | 3M Scotchlok Quick Splice with Gel (14 AWG stranded) | We used that to parallel our LED lights (25 Pack) | 1 | View |
8 | Heat Shrink Tubing Kit (with adhesive) | To protect lug after crimping | 1 | View |
9 | Split Loom Tubing, 3/8″ diameter 25 feet | To protect wire bundles | 1 | View |
10 | Split Loom Tubing, 1/2″ diameter 25 feet | To protect wire bundles | 1 | View |
11 | Split Loom Tubing, 3/4″ diameter 10 feet | To protect wire bundles | 1 | View |
12 | Nylon Cable Clamps Kit | To secure cable/split-loom to wood | 1 | View |
13 | Zip Tie Mount with Adhesive | To secure cable/split-loom to metal | 1 | View |
14 | Nylon Zip Ties Kit | To secure cable/split-loom | 1 | View |
15 | Rubber Grommet Kit | To protect wire from sharp edge (going through metal hole) | 1 | View |
12V Loads
These are the appliances we personally use in our van:
# | Item | Quantity | Buy Link | More Info |
1 | Maxxair 6200K Roof Fan | 1 | Amazon | Fan Installation |
2 | LED Ceiling Lights (Dimmable) | 3 | Amazon | |
3 | PWM Dimmer for LED Lights, 12V, Slider | 1 | Amazon | |
4 | Blue Sea 12V Socket | 4 | Amazon | Electrical System Guide |
5 | Shurflo Revolution Water Pump, 3 GPM | 1 | Amazon | |
6 | ON/OFF Switch for Water Pump | 1 | Amazon | |
7 | Webasto Air Top 2000 STC Gasoline Heater | 1 | eBay | Webasto Installation |
8 | Propex HS2000 Propane Heater | 1 | Dealers | Propex Installation |
9 | Novakool R5810 Fridge, 12V only | 1 | Campervan-HQ | Fridge Guide |
10 | Sirocco ii Gimbal Fan, 12V | 1 | Amazon | Sirocco ii Installation / Review |
11 | Nature’s Head Composting Toilet | 1 | Amazon | Toilet Installation |
12 | Propane Solenoid Shutoff Valve | 1 | Amazon | |
13 | ON/OFF Switch for Propane Solenoid | 1 | Amazon |
Tools
These are essential to build your electrical system. Do NOT cheap out on tools (e.g. using pliers to crimp) or you'll compromise the performance and safety of your system.
# | Item | Description | QTY | View on Amazon |
1 | Crimping Tool, Single-Crimp (8-22 AWG) | Single-Crimp should be used with Heat Shrink connectors to prevent tearing the insulation and loose the watertight connection (corrosion prevention) | 1 | View |
2 | Cutter / Stripper for 10-22 AWG Stranded Wire | Nothing to add! | 1 | View |
3 | Hydraulic Crimping Tool (2/0-12 AWG) | Provides adequate, repeatable results for larger gauge lugs. | 1 | View |
4 | Cutter for up to 4/0 Cable | For large gauge cables | 1 | View |
5 | Heat Gun for Heat Shrink Connectors | 1500W, Dual Fan Speed, Variable Temperature Control | 1 | View |
6 | Digital Multimeter (Voltage, Current, Continuity, Resistance) | You don’t need it until you need it! Your friend when you need to troubleshoot… | 1 | View |
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about us
Nice To Meet You.

Hello! We’re Isabelle and Antoine In 2017 we sold our house (and everything in it), quit our engineering careers and moved into our self built campervan. We’ve been on the road since then and every day is an opportunity for a new adventure; we’re chasing our dreams and hopefully it inspires others to do the same!
The van electrical calculator seems to be missing the spot to plug in what will be being used.
Awesome info on your website. I am building my van now. First time in the winter as well…. and pandemic and crazy USA situation! anyway , do you have any great ideas for hot water heater that uses minimal electricity? I am looking at the mini 2.5 gal Bosch, but even that uses 1450 Watts. I could get a 2000Watt inverter, and I only need 20 minutes to heat there water for a shower every other day ( song bath in between or friends house if needed). I am trying to stay away from propane ( just a 1 gal bottle for my cooker). I am new to this and would appreciate your help if you know of anything MUCH OBLIGED!!!
Thanks for compiling this!
The Sterling Pro Batt Ultra B2B Charger is unavailable on Amazon (not just out of stock). I did however find the Renogy 60A DC to DC Battery Charger, is that an acceptable replacement?
It’s acceptable but not equivalent. More info about it here: https://faroutride.com/b2b-review/#Runner-Up
Hi folks, let me say I have probably funded your next trip since I not only bought your builder’s pack but have spent about $4500 so far on Amazon using your affiliate links! But now I have two questions if you don’t mind helping me out. First, I bought the Samlex 1230 based on your calculator even though so many forums say not to use this with a LiFePo battery. But you do so I’m trusting your experience. What DIP settings are you using? In the manual it looks like I should use “battery with load” both dip off but I have a feeling you’re using S1 off, S2 on, Flooded/AGM. Can you please enlighten me so I don’t blow my batteries up?
Second, your calculator in Acrobat Pro doesn’t show a fuse between the hot bus and the 2000 watt invereter but Mac Preview (which I know your calculator doesn’t support) shows a 250 amp Bussman battery terminal fuse between the bus bar and the inverter. I assume that is correct?
Thanks!
First, thank you for your support, it means a lot 🙂
Samlex 1230: S1 off/S2 on, LiFePo4 battery charging profile is similar to AGM battery, so no issues here.
The wire between the bus bar and inverter will be protected by the 250A fuse that is located between the battery and the bus bar. However, if that fuse blows up because something goes wrong with your inverter, your whole electrical system is down. Having a fuse between the bus bar and inverter could isolate issues with your inverter from the rest of your system; assuming this is the one to blow!
When going with a smaller inverter, wire can be smaller and must be protected by a smaller fuse (175A/200A).
Thank you so very much, that’s just what I needed! One thing I do see missing from your site (and this might be planned) is any photos of your electrical system. I can look at your calculators but was hoping to find some photos of how you laid yours out. I watched your video of the van tour but it only shows Antoine opening a tiny cabinet then closing it again. I can’t believe all of those wires, components and breakers fit in that tiny cabinet. At any rate, your site has been indispensable and I am creating my entire electrical system and propane system directly from your diagrams. What an amazingly helpful resource.
Just stopped to say what a wonderful website full of some of the best info around.
Thank You!
Is it possible that there is an error in the AH calculation in the 120 volt section of your electrical calculator. I have always though that the wattage needs to be divided by the voltage to obtain the amperage. In the calculator, the wattage is divided by 12 instead of 120. Am I wrong?
But remember that your energy source (the battery) is 12V!
– So between the battery and the inverter (where the voltage is 12V), the current is AMPS=WATTAGE/12V (and in fact, even more amps because of the efficiency loss of the inverter);
– Between your appliance and the inverter (where the voltage is 120V), the current is AMPS = WATTAGE/120V
Hope that makes sense.
We have the same question…
When we type in 1050 watts for our microwave for 0.25 hours it gives us 27.5 amp hours. This doesn’t seem possible… Whereas if we divide by the 120V it then gives us 2.57 amp hours.
Just looking for further clarification on this.
Thanks
Here is the calculation:
Current as seen by the inverter (120v): Amps = Watt/Volt = 1050W/120V = 8.7.A
But look at what’s going on at the battery bank:
Current as seen by the battery bank (12v): Amps = Watt/Volt = 1050W/12V = 87.5A
Total energy draw at the battery bank: Ah = A * h = 87.5A * 0.25h = 21.9Ah
The calculator also includes conversion loss (120V > 12V) from the inverter of 85%: 21.9Ah/0.85= 25.7Ah
So using your microwave for 15 minutes draw 25.7Ah from the battery bank. If you start with 200Ah (2 batteries at full charge), the remaining energy left in your battery bank is: 200-25.7 = 174.3Ah. So you went from 100% charge to 87% charge.
Hope that clear things up!
antoine
First, thanks for making such a helpful guide. I was wondering, what made you choose the 60A b2b charger if your alternator could theoretically handle more. We have a transit with a 250A heavy duty alternator, and we’re big time snow chasers, so we figure the more we can pull from the alternator in the winter, the better. is there anything dangerous about going with a 100A b2b?
We were also wondering, do you think it would be possible to route the b2b through one of the transit auxiliary switches? The idea would be to try to use it less in the summer when we can count on solar to save wear and tear on our alternator, but turn it on in winter or any other time we need the boost. Is there any merit to that idea?
Thank you so much!
First, we don’t think it is dangerous to go with a 100A B2B. We wanted to go with Sterling and they don’t recommend using the 120A for automotive application. We felt 60A was enough for our needs.
As for the auxiliary switches, they won’t provide enough current. And since we installed breaker before and after the B2B, we simply use them to shut down the B2B charger (it can also be done on the charger itself). This article will provide you with more information about our installation: faroutride.com/b2b-review/
Wow… just wow. You guys have created such an incredible resource here and I’m so thankful. This would take me uncountable hours to figure out if I were piecing it together from all the different web sources. I think I may build my entire van out using the resources you’ve created, so THANK YOU! I’m so impressed at the level of detail you guys go to, and the electrical usage calculator with autofill options might be the coolest thing I’ve seen yet. Thanks again for everything you guys have created, super stoked to build our van, and we’ll be sure to use your Amazon affiliate links for everything we can!
I purchased the van electrical calculator, but it doesn’t appear to work for me. It says I need more than 500Ah of battery and more solar than your calculator can handle, so I’m not getting the component or wire gauge calculations that I need. What can I do?
Can you provide a screenshot of the calculator with your inputs? Otherwise it’s hard for us to advise…
You can send it to faroutride at gmail dot com.
Cheers
Hi and thank you for such amazing resources!
When calculating needs, my setup estimates 46ah per day, however recommends 200ah lithium batteries. Since lithium can be used completely, can you explain why 100ah wouldn’t be sufficient?
Thanks so much!
You could go with one (selecting Sun Seeker option should also give you 100Ah). However, it doesn’t give you a lot of autonomy in case you can’t charge everyday.
For the Main Component Sizing, what are some of the assumptions? Is it assuming 2-days capacity? I came up with 190Ah usage. In Sun Seeker mode with Lithium battery, it recommended 400AH battery capacity, or 600AH AGM. I’m sure it’s making assumptions about re-charge from solar, solar panel efficiency… But is it assuming more than one day worth of capacity?
Hi! For reference, this page goes through the calculation step-by-step (including the formulas): https://faroutride.com/van-electrical-sizing/
You’ll find in section 3.1.2 that the formula for Sun Seeker lithium is: Battery capacity=(Daily Power Usage x 1.5)/0.8.
190Ah usage seems unusually high… Can you take a screenshot of the calculator (with your inputs) and send it to faroutride at gmail dot com ?
Hi there! I am so very impressed with people like you who have such detailed knowledge like this. I kind of make it up as I go and learn along the way 🙂
Anyway, I am in a learning phase right now. I have a 90w fridge that runs 7.5 amps and two macbook pros between my gf and I. That would need some charging mot days. 2 iPhones and a camera and drone with batteries.
We have 160W solar and 2, 100ah AGM batteries that are also connected, in parallel, to a split charge system. Would love your thoughts on if you think our system will be adequate? TIA!
Hi Antoine and Isabelle, why is a terminal fuse block included in the ‘inverter’ section with a 1000W and 1500W inverter, but not with a 2000W inverter? Thanks!
Because the wire between the inverter / bus bar is already protected by the 250A fuse (located at the battery terminal). When you choose a 1000W or 1500W inverter, the smaller wire is not rated for up to 250A and therefore must be protected with a smaller fuse. Hope that makes sense!
We used your old calculator (love the new one though!) and ended up with a 600W inverter and 100Ah battery. We just decided we wanted to use the Pakt coffee kit in our van which has a kettle that draws up to 500 Watts. I’m worried that we should’ve gotten a 1000W inverter now… Do you think we can still get away with using our 600W inverter and 100Ah battery? We use an alternator charger and drive at least an hour a day so I’m not too worried about having power, just don’t want to ruin our system trying to draw too much… Thank you for any advice!
I’d give it a try, you won’t damage your system. Here’s what will happen if you have an overload (extract from the Samlex manual):
10.1.2 Overload: If there is a continuous overload of 110% to 115% for 2 to 3 sec, the
output voltage will be shut down. Red LED marked “OVERLOAD” (3, Fig 6.1) will turn ON,
the Status LED on the GFCI outlet (5C, Fig 6.1) will be OFF and buzzer alarm will sound.
The Green LED marked “POWER ON” (2, Fig 6.1) will continue to be lighted. The unit will
be latched in this shut down condition and will require manual reset. To reset, switch OFF
the unit using the ON/OFF Switch (1, Fig 6.1), wait for 3 minutes and then switch ON the
unit again. Before switching ON, determine and remove the cause of overloading.
Isabelle, Antoine,
First off, you two are beasts for compiling everything on this website. Couple of inquiries for you: Please explain the need for the 250-amp catastrophic fail safe. Considering a system where the only input is 540-W of solar with the respective Victron 100/50 MPPT with the Battle Born BMS’s and the assorted circuit breakers, is the fail safe necessary? Seems like there is plenty of redundancy with respect to fail safes.
Additionally, the shore power charger by Samlex you recommend is apparently not intended for Li cells per the manufacturer’s manual. Is there a 120-12v converter you like or have heard about for the popular battle born batteries?
Thanks!
Andrew
The 250A fuse would be useful in the case of an accident, or even during installation if pos/neg cable touch by mistake; that’ll protect you from getting electrocuted or starting a fire.
Battle Born FAQ mentions that a charger with AGM settings works fine, since the charge profile is very similar.
Cheers
How are you calculating the fridge only being active for 8.4 hours a day? is it assuming this is the amount of time that the system is not running from Solar?
Thanks,
Hey Kieran,
most campers are using a compressor fridge, that means the fridge only consumes power when the compressor is working. Over the day, it is only active for a few hours (depending on the outside temperature) and the rest of the time the cold is stored.
I hope I could help you too