Made with in our van.

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short url: faroutride.com/calc
Calculator and diagram workflow:
FarOutRide-Illustration-Cross-Section

Van Electrical Calculator

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


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.
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 wire gauge, fuses & breakers to ensure that your own system is safe and performs as it should. Bonus: it also calculates all the wire 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!

3- Customize Your Items list

Fill these tables per your wiring diagram:

WIRES LENGTH (FT)

AWG4/03/02/01/01246810121416
RED
BLACK
DUPLEX

TERMINALS QUANTITY

AWG4/03/02/01/01246810/1214/16
#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

Heads up! There are now cheaper alternatives to Battle Born Batteries. You will find a list of our recommendations here: faroutride.com/battleborn-alternatives

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
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:

#ItemQuantityBuy LinkMore Info
1Maxxair 6200K Roof Fan1AmazonFan Installation
2LED Ceiling Lights (Dimmable)3Amazon
3PWM Dimmer for LED Lights, 12V, Slider1Amazon
4Blue Sea 12V Socket4AmazonElectrical System Guide
5Shurflo Revolution Water Pump, 3 GPM1Amazon
6ON/OFF Switch for Water Pump1Amazon
7Webasto Air Top 2000 STC Gasoline Heater1AmazonWebasto Installation
8Propex HS2000 Propane Heater1DealersPropex Installation
9Novakool R5810 Fridge, 12V only1Campervan-HQFridge Guide
10Sirocco ii Gimbal Fan, 12V1AmazonSirocco ii Installation / Review
11Nature’s Head Composting Toilet1AmazonToilet Installation
12Propane Solenoid Shutoff Valve1Amazon
13ON/OFF Switch for Propane Solenoid1Amazon
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.

#ItemDescriptionQTYView on Amazon
1Cable Cutter (up to 4/0 AWG)For large gauge cables1View
2Wire & Cable Cutter (2/0 – 22 AWG)Nothing to add!1View
3Wire & Cable Stripper (4/0 – 20 AWG)Nothing to add!1View
4Hydraulic Crimping Tool (4/0 – 10 AWG)Provides adequate, repeatable results for larger gauge lugs.1View
5Crimping Tool, Single-Crimp (8 – 22 AWG)Single-Crimp should be used with Heat Shrink connectors to prevent tearing the insulation and loosening the watertight connection (corrosion prevention)1View
6Heat Gun for Heat Shrink Connectors1800W, Variable Temperature Control1View
7Digital Multimeter (Voltage, Current, Continuity, Resistance)You don’t need it until you need it! Your friend when you need to troubleshoot…1View

Want More?


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About us


NICE TO MEET YOU.

About-Us-Narrow

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. Every day is an opportunity for a new adventure... We’re chasing our dreams, and hopefully it inspires others to do the same!

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Thanks to all of you, we managed to negociate group discount on these. Strength in numbers!

163 thoughts on “Van Electrical Calculator”

  1. Hi Antoine,

    You guys truly struck gold with this site. Well done! I noticed when using this calculator that the MPPT charger selected for me is the 150/60, which I believe is rated for 60A, but the suggested breakers to use are 70A. Why would that be? Thanks!

    Reply
    • 60A would be consider within normal range operation, so a 60A fuse could blow during normal operation. Overcurrent protection are generally 15-25% higher than the device (MPPT in this case), then the wire is sized accordingly to the overcurrent protection.

      Hope this makes sense!
      antoine

      Reply
  2. Your web page is an excellent resource and my thanks to both of you for putting it together.

    I have one question I’d like to get your input on. I’m using your high power wiring diagram. It is my understanding that the protective device (i.e. breaker or fuse) should be located near the source of power for the cable it is protecting. The wiring diagram depicts the 400A fuse associated with the Victron inverter and the 60A breaker associated with the output of the MPPT controller inside the “Main” block close to the bus bar. I’m not sure this implies those devices should be located near the respective bus bar. My question is should the respective fuse and breaker be physically located close to inverter and MPPT controller respectively or am I mistaken on what the fuse and breaker are protecting?

    Thanks

    Reply
  3. Hey, I am planning a high-powered build (including 1800W induction, 12V-fridge) for use as all-season van-home resulting in an estimated daily use of 109Wh; I just bought a used fuel-cell from efoy (the 80Ah/d version) – how would you think that alters the requisite battery and solar dimensions? My gut feeling is it takes away 100-150Ah of estimated battery needs (which would otherwise be 340ah) and lowers the solar need by a similar wattage (as you can additionally charge 80Ah with the fuel cell even on stationary cloudy/snowy days)?

    Reply
  4. I am following your plans for a “snow chaser” setup and when looking at battle born batteries I noticed that they now have heated battery kits for colder climates. For the added cost, do you think this is something worth including? My van will be in Colorado full time. Thanks!

    Reply
  5. I am learning so much! What I am worried about is mixing this with a Skoolie, 27ft bus, how interchangeable would this system be with a bus?

    Reply
  6. Question: I have 2015 Transit diesel with duel “heavy duty” batteries; however, the window sticker sheet makes no mention of type/s of alternater (I always thought they were called generators for diesel). Anyways, should I use 30A or 60A B2B?
    My 350 duelly was purchased as a standard ‘fleet’ vehicle with no bells or whistles. Trying to finally upgrade this van properly after ripping everything out due to mold attack after 5 years of use (cheap setup with shore power via extension cord; fan-tactic fan powered by gel battery, 90 watt solar with 8 amp charge controller. No other features. Goodbye).
    Your website and your builders package is really getting my brain in shape. Thank you. Geoffrey

    Reply
  7. Hey! I was looking at the Wiring Diagram versus the Electrical Calculator Shopping List and noticed that an item between the Batteries and the Bus Bar going towards the Fuse Block is not listed. Is this item not absolutely needed? If it is, what would that item be?

    Thank you for putting this all together. You guys are awesome and if you’ve seen a surge in views in Arkansas, that would definitely be me! I’m slowly piecing the electrical all together and almost done with my plumbing!

    Reply
    • A SHUNT. A shunt is required only if you opt for a system monitor (e.g. Victron BMV-712, Simarine). The shunt is included with the system monitor, that’s why you don’t see it in the items list 🙂

      Antoine

      Reply
  8. Hi there! Thank you for all of the great information. I purchased the interactive package and am unable to see any changes made to the diagram on Adobe when I try to change the options from the drop down menus. I am on a computer for this, but nothing on the diagram changes for me when I change the options. I followed all the steps on the tutorial, but no luck. What am I doing wrong? Thanks for your help!
    Vinnie L.

    Reply
  9. Hi!

    Like many have expressed – I’d be adrift without your resource. I’m plugging away with minimal frustration and a building confidence. I followed your lead for a pair of longer run 12V sockets but I’m uncertain how to connect wire to outlet (I can’t seem to find any 8AWG female disconnects)?

    Also, did you keep any outlets on the same circuit (i.e. could I wire the above mentioned outlets together?)?

    Thanks for any guidance you can offer. Before it’s all said and done, I’m having my work checked by an auto electrician for peace of mind. Onward!

    Reply
  10. I bought the build package which has been a great help but can’t seem to get the wiring diagram wire sizing to function on my iPad Pro to work. I assume I should be able to change wire lengths on the diagram.

    When I am sure of my wire size I plan to order from Amazon and want to make sure you get your commission so if I go directly into Amazon from your diagrams etc that will insure that would occur?
    Do I put everything in a cart then checkout through my account?

    Reply
    • Hi Mark, thanks for your support!
      Unfortunately interactive features do not work on phones or tablets; you must use a computer. This is an Adobe limitation we don’t have control over 🙁

      Using any Amazon link on our site will work, or you can use this link to search for products and we’ll also get a commission: https://amzn.to/3xVSefL
      Thanks for asking 🙂

      Reply
  11. Terminal Fuse Block with Fuse 250A Blue Sea (Catastrophic Fail Safe. Connects directly to battery post.) This is the first item on my ‘shopping list’. Amazon is providing a choice of 225 A and 300 A there is no 250A to select. So, which one should I use?

    Thanks Kim

    Reply
    • Looks like the 250A is out of stock at the moment. You can try other than Amazon, look for : “Blue Sea Systems Battery Terminal Fuse 250-AMP”
      Do NOT go for the 300A instead.

      Good luck,
      antoine

      Reply
  12. Hello, thanks for all the great info and resources. I had a couple of questions with the High-Power diagram. I was looking to install 400 watts of solar on the roof. I don’t see that as an option in the diagram and wondered how that would change the wiring size from the charge controller to the bus bars. Also, I am stuck with understanding the 300A fuses between the system and the batteries and the one between the system and the Inverter/Charger. How are those sizes determined.
    Thanks again. I look forward to your answers.

    Reply
  13. i am unable to figure out how to get my electrical choices on an electrical diagram. Does it create a custom diagram or just a parts list?

    Reply
    • The calculator generates a custom parts list (just scroll down this page to see it); for the wiring diagram, after you download and open it in Acrobat Reader, you’ll have to manually input the value of solar, shore, inverter, etc., because it cannot be done automatically (it’s an Adobe limitation).

      Cheers,
      antoine

      Reply
  14. Hi, thanks for all your great information. I am planning a big electrical upgrade on my camper and I purchased your high-power wiring diagram to assist with the design. I do have a couple clarifying questions I am wondering if you could address. First, why are there 2 Class T fuses in the system between the Multiplus and battery bank? Is this necessary? Also you place a class T fuse (400 amp in my case of a 3000 watt Multiplus) between the battery and disconnect switch. Would it not be better to place the disconnect first and then the fuse, so if the fuse ever blows the switch can be shut off and you will not be working on a hot wire? Anyway, would like to get your input on this as I am making the final adjustments to my plan.

    Reply
  15. I’m so lost I don’t even KNOW how to begin to tackle all of this! I’ve been studying up and doing so much research but it’s just NOT clicking yet. These tools are so helpful, so thank you for taking the time to do this so beautifully!

    Reply
  16. 120V Daily usage equation shows [(Power/12) * hours]/0.85

    Shouldn’t this be [(Power/120) * hours]/0.85 ?? (Watts/120v)

    Thanks – great website!

    Reply
  17. Isabelle and Antoine,
    A big THANK YOU for providing us with all of this excellent information and also for continuing to update as you learn more and gain experience with your designs.

    I have a couple questions:
    I have two 100Ah lithium batteries and just purchased a 30A Samlex Smart shore charger per your recommendation. I just realized that Samlex recommends this charger for lead-acid batteries. Will it work well for lithium as well?

    On your wiring diagram, you have two 12V sockets, and the wire you selected (12/2 AWG for 15 feet and 8/2 AWG for 30 feet) seems really thick for a 12V socket, especially the 8/2. Is this just to enable the use of something that has a big draw rather than just charging a phone for example?

    Hope you’re getting some fresh lines this year. We’re having a pretty good season here in Taos, NM.
    Marcus

    Reply
    • I know 8/2AWG looks like a really big wire, but we didn’t want to “remember” this socket can’t take to much by limiting the wire/fuse. And if we ever sell the van, we know it is safe and functional.

      As for the Samlex question, I think this comment will give you the answer you are looking for.

      Good to hear you’re having a good season in NM 🙂

      Reply

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