First time electric build

[grahampa]

Hi all. Was just considering my new electric system and trying to create a wiring diagram. Watching Greg Virgoe on YouTube gave me some great ideas to have a sort of controller which allows me to access either solar or shore power. Planning on running a fridge, heater ignition, stovetop ignition, lights, vent, fans and have some plugs for small appliances or laptop. Plus eventually looking to add a water pump but not immediately. Definitely want to splice off of the alternator to charge while I drive as well. How many batteries will I need? Will I need a new alternator if mine is from a 2002? The van is completely stripped so what wires do I absolutely need to run before installing insulation?

Thanks for your input in advance!

 

[Almost There]

First start with an assessment of projected power usage. This means listing everything you think you're going to want to run off the battery bank, noting how much time it will be used each day and figuring out how many amp hours of power you need for each.

The total will then tell you how big a battery bank you are going to need. Depending on the type of batteries you choose to use, you will then know the size of the battery bank needed.

Working from that you can tell how much solar you're going to need, how many spots in a 12V fuse panel you'll need, how big a battery charger you'll want to put in (or use portable) and what size of inverter (if you want one) you'll be able to comfortably run from the battery bank.

I can almost promise you that you will re-work the specs multiple times as you find out that you a) don't have enough roof for that much solar and b) what you THINK you want to run will cost way more than you initially planned on spending....

Oh and one doesn't 'splice off the alternator', one puts in a continuous duty solenoid that allows the alternator to charge both the house battery bank and the engine battery at the same time while preventing the engine battery from being drained by house/coach usage.

 

[B and C]

^^^Good advice.

When you figure out you Ah use per day, double it and that is the smallest battery bank you can have. This is under ideal conditions. There are rainy days where you won't get a full charge. You might want to tripple that for worst case scenarion. I run 350 Ah's worth of batteries which give me 175 usable Ah's.

 

[grahampa]

Wow thank you so much for the info! That's a fantastic start. I will look more into the solenoid, thank you. I'm excited to get my rough draft done tomorrow! Thanks again!

 

[sephson]

Something else you should do is take measurements of your roof to figure out how much space you have available for solar panels. If there are any roof vents or other items, or if you plan to add roof vents or other items, you need to take these into account. If necessary, break the roof down into sections and measure these individual sections. Once you know how much area you have for the panels, it's time to start researching panels unless you already know what you're going to install.

When I did my solar install, I went with two Renogy, 100 watt Polycrystalline panels, not because I thought they were better than other available panels, but because they were the best fit for the space I had available on my roof.

If you want to have any extra panels that you set up outside, away from the vehicle, you need to take these into account when you choose your charge controller. Other more knowledgeable members of the forum than me could give you better information on this part of the process.

 

[grahampa]

Well I decided to go with a 300 amp hour system I am in the process of buying a solenoid, some wiring casing, the batteries themselves (three 100AH agm deep cycle), my vent, the fridge, an inverter and other. What wire gauge size will I use for my batteries? I will add solar as I can afford it, probably two months from now. Should I wait until then to buy a charge controller?

 

[Almost There]

What are you planning on using to keep those batteries charged up until you add solar?

Wire size will depend on where the batteries are in relation to whatever charging system(s) you're using, bigger is better in the case of wires. All wire sizes really depend on what they are running to/from and how far each is from the other.

The size of the inverter will determine what size wire you are needing.

And yes, the controller and the solar panels should be bought at the same time to prevent you from having bought the wrong controller for the solar panels you end up getting.

i don't see any mention of fuses in the shopping list.

Also, what fridge are you intent on buying?

 

[bullfrog]

In order to know what guage of wire to use you will need to know how long they will be, the longer the wire the thicker it must be, usually it is estimated oversize if one can afford to do so to make it possible for a little future expansion of the system without having to replace the wire. Things like battery placement, how far away from the batteries the inverter is, how far the solar controller is from the batteries and whether solar cells will be perminently mounted a certain distance from the controller or portable all can make a difference.

 

[grahampa]

This electrical stuff sure is a nice challenge. I just purchased a continuous duty solenoid 150a, 1/0 gauge copper wire, 2 100ah batteries, shore power hook up and a roof vent. Looking into inverters now. This stuff gets expensive quick! 

For my lights I plan to use 18 - 20 gauge wire. I suppose the vent would need about 14 gauge wire. The fridge I'm planning to buy should be 14 gauge wire too. Speakers will be on 14 gauge most likely, 12 for subwoofer.  TV will be on 14 gauge. Will add wiring for water pump as well at 14 gauge. 

The inverter should be enough to power about 40amps peak usage (cooking w/ blender(at right times), rice cooker, toaster, phone, laptop) so I guess I'll look for one for 50 amps and use 6 gauge wire for it? The plugs I run from the inverter should use 14 gauge wire as well, correct? Hope I'm getting close to understanding this. Every appliance will have a fuse as well to stay as clean and safe as possible

 

[Matildas mate]

**First start with an assessment of projected power usage**

Northern Arizona Wind & Sun’s website has this nifty online calculator to help determine your solar needs...

https://www.solar-electric.com/solar/calc/

 

[Almost There]

This electrical stuff sure is a nice challenge. I just purchased a continuous duty solenoid 150a, 1/0 gauge copper wire, 2 100ah batteries, shore power hook up and a roof vent. Looking into inverters now. This stuff gets expensive quick! 

For my lights I plan to use 18 - 20 gauge wire. I suppose the vent would need about 14 gauge wire. The fridge I'm planning to buy should be 14 gauge wire too. Speakers will be on 14 gauge most likely, 12 for subwoofer.  TV will be on 14 gauge. Will add wiring for water pump as well at 14 gauge. 

The inverter should be enough to power about 40amps peak usage (cooking w/ blender(at right times), rice cooker, toaster, phone, laptop) so I guess I'll look for one for 50 amps and use 6 gauge wire for it? The plugs I run from the inverter should use 14 gauge wire as well, correct? Hope I'm getting close to understanding this. Every appliance will have a fuse as well to stay as clean and safe as possible

yes, it can get expensive. Although as compared to paying the electric bill for years and years and years, once you're past the initial investment, it gets way cheaper.

I found it easier to just buy all one gauge of wire - I used 10 for everything. It is definitely overkill for LED lights but cheaper to buy 100' foot rolls of one gauge than to buy smaller quantities of all kinds of different wire. Also remember that you'll need twice the distance for each wiring job - I bought equal amounts of black and red.

Inverters are rated in Watts, not amps. Make sure you add enough wattage to cover the start up surge of many appliances. Wiring to the inverter from the batteries needs to be fairly hefty, I don't think 6 guage is going to cut it but it will depend on the size of the inverter. I wired the plugs FROM the inverter to duplex outlets in the van with regular 12/2 romex although  many will tell you that using solid strand wire is not recommended for a mobile application and one should use multi strand wire like you'd find in an outdoor extension cord (which could be a good solution).

Actually one doesn't fuse the appliance, one puts fuses in to protect the wiring.

 

[grahampa]

Thanks guys.

Fuses and trips / circuit breakers can be used interchangeably correct?

What are the differences between having two 100ah batteries and one 200ah battery? Any major disadvantages to either?

For now I am hoping to use less than 50 amps a day, and don't plan to install solar for a few months. I plan to charge off of the continuous duty solenoid I bought and use shore power when possible. In interest of time and getting into my van as soon and as cheap as possible I will wait on the inverter as well. Everything major will run fine on DC for now, my fridge, vent, speakers, lights and eventually pump (fridge has usb slots for phone & accessory charging).

Oh and I ended up buying 100ft 12 gauge ofc dual red and black wires for most plus a roll of 20 gauge for smaller things such as lights.

 

[highdesertranger]

I will let some one else answer the fuse/circuit breaker question. I use both.

the big difference for me with the batteries, two batteries gives you redundancy if one fails you still have power. reduced power but you are not dead in the water.

you do realize that you must drive for hours and hours at highway speed to fully recharge a house battery bank off of an alternator. idling will not cut it and if you take your battery down to 50-60% you are looking at 7+ hours of driving at highway speeds.

highdesertranger

 

[Trebor English]

Fuses and trips / circuit breakers can be used interchangeably correct?

I have used an automotive breaker.  It looked like the same terminals as a fuse.  The pins are thicker.  The contacts in the fuse box were spread.  After that fuses were loose in that spot.  I bought a new fuse box.  Automotive fuses and breakers cannot be interchanged repeatedly.  

Federal Pacific Electric, FPE, is a company that has vanished.  They got sued out of existence because they sold a butt load of breakers that didn't trip.  Breakers have moving parts and can (and sometimes do) fail.  By fail I mean fail to open the circuit during an over current event.  

Fuses use a soft high resistance low melting point bit of wire.  When there is too much current the wire sags and gets thinner then quickly the resistance goes up and poof, there is an open circuit.  Simplicity.  

During normal conduction fuses have a lower voltage drop than an equivalent breaker.  

Sometimes people say that breakers are better because they are easy to reset when they trip.  My opinion is that making it difficult to reset will make it more likely that the underlying over current cause will get fixed rather than ignored.  

Fuses are less expensive.  For some people that means they contain less goodness so they must be inferior.  I prefer less expensive.

 

[grahampa]

What if I could charge daily on shore power while I'm at work? honestly when I start off I'm going to have a very basic setup using lights fan and possibly the fridge when I can afford it. That's about 30 amps a day, how long would that take on shore power? 

I am installing wiring for my solar system before I start living in the van anyway so I will get it asap, if I have to return a battery to Walmart cuz I killed it I won't be that upset. Believe they have 2 year warranties.

 

[Matildas mate]

I’m going to assume that the fast charge stations available for electric vehicles will not work with most solar setups but I’m wondering if the technology is available that could make it work in the same way that shore power would work at a campground. Does anyone have any expertise regarding if these charging stations could ever be utilized to charge house batteries?

 

[highdesertranger]

oh no not again. we just had a rather heated discussion about Electric Vehicle(EV) charge stations. form all the info I found they are for EV's only, no exceptions. nobody has come with any info to the contrary, however we would welcome any confirmable info on the charging stations. highdesertranger

 

[Matildas mate]

oh no not again.  we just had a rather heated discussion about Electric Vehicle(EV) charge stations.  form all the info I found they are for EV's only,  no exceptions.  nobody has come with any info to the contrary,  however we would welcome any confirmable info on the charging stations.  highdesertranger

Was that on this thread, i didn’t see it. Could you link me to the heated discussion? I’d like to read it.

 

[highdesertranger]

you asked for it, here you go,

https://vanlivingforum.com/showthread.php?tid=34337&highlight=tesla+battery

note some of the more colorful posts have been deleted.

highdesertranger