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Drafting a VanLife system - thoughts on this system? Specific questions under the diagram

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clammchops

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Joined
Feb 22, 2022
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18
electrical_diagram2.png

--
A few questions that I have:
  1. Should this be a 12V system or a 24V system?
  2. I am not sure on the solar size yet as it depends on the room on the roof. I am thinking somewhere between 500-800W, how will this range change what I need to do in the diagram?
  3. Is there a more efficient way to wire this?
  4. I do not know what size breakers/fuses to use, and if I have enough or if I have too many - thoughts?
  5. Where would grounding wires go in the diagram?
  6. Any other feedback/comments/concerns with this setup?

UPDATED DIAGRAM, LIST OF KEY ITEMS IN THE SYSTEM, AND QUESTIONS BELOW:
electrical_new.png
SOLAR:
Alternator:
Shore:
Batteries:
Miscellaneous:
Questions:
  • Solar:
    • Do I wire in Series or Parallel?
    • Is a 50A breaker sufficient for the solar?
    • If I wanted to add a third panel (the same kind), would the system support that?
  • Alternator:
    • Is the 30A breaker correct, or is there a cheaper/better solution for this? How would you add a 30A fuse on both power wires?
  • Shore:
    • Is a 30A breaker larger enough?
  • All:
    • Is the wire gauge correct for all of the connections?
    • Is the Lynx Distributor an effective solution, or are there better/cheaper options?
    • Is the Battery Monitor needed, or is there a better solution?
      • Maybe... Instead of the Smart Shunt/Batter Monitor, how would I incorporate a Cerbo GX and Touch?
 
Last edited:
Breakers or fuses for over current protection are only needed in the positive paths.

In a metal body van the 'ground' is the van metalwork

The decision for a 12 or 24 volt system rests usually of how much power you will be using with the inverter. Although you show a 3000 watt inverter, just how much AC load do you expect to need?

Your diagram and parts identified are for a 12v system with the batteries wired in parallel, the Renogy dc to dc and MPPT charger is only usable for a 12 volt system with maximum of about 400 watts of panels.

If you decide on a 24 volt system you will need the panels configured to give a higher voltage to the solar charger.

With a 24 volt system the batteries will be in series so you will need a 24 to 12 Dc to Dc converter for the 12v dc appliances.

A 24 volt inverter for 3000 watt loads is practical, if the actual power needed is lower then a 1500 watt inverter is usable on a 12v system.

I suggest before proceeding, evaluate your actual need for 3000 watts of AC power.. If you need the 3000 watts then a 24 volt system is more practical. However this needs more parts, a DC to DC, 24 to 12, and a different solar controller, panel configuration and engine DC charger.

With the inverter and a permanent install with distributed AC wiring and multiple appliances and outlets there is a risk of electric shock. A earth leakage protection device is needed and to ensure this will operate correctly the inverter needs a neutral to protective earth bond at the inverter. The inverter installation literature should have details. The AC protective earth connects to van 'ground'.

You may wish to consider an inverter charger. This has auto switching between shore and battery power for the AC system, makes things easier for the AC side and looks after the neutral bond


Mike
 
You have 7,680Wh of battery but only 300W of solar. It would take over 25 hours of perfect solar conditions to fully recharge your batteries. Given that your panels will likely be flat mounted on the roof then it will take even longer. The fact that you can charge via the alternator does help offset this mismatch.

Do you really need a 3000W inverter? What do you plan to run on AC that requires so much power?
 
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clammchops said:
--
A few questions that I have:
  1. Should this be a 12V system or a 24V system?
  2. I am not sure on the solar size yet as it depends on the room on the roof. I am thinking somewhere between 500-800W, how will this range change what I need to do in the diagram?
  3. Is there a more efficient way to wire this?
  4. I do not know what size breakers/fuses to use, and if I have enough or if I have too many - thoughts?
  5. Where would grounding wires go in the diagram?
  6. Any other feedback/comments/concerns with this setup?
Click to expand...

Should this be a 12V system or a 24V system?

Most of your items are DC and the inverter is 3000W which is on the cusp of whats viable/sensible for 12V. I have similar use but a 2000W inverter and I'm going 12V

diysolarforum.com

My Build Questions - Camper Van 480W Solar 12V 200Ah LifePo4

Finally starting to install this system Purchased Product Specifications Battery – SunnyTech (badged Lithium Valley) 12V 200Ah Lifepo4 https://web.archive.org/web/20210130064931/https://sunnytech.co.nz/store/default/product-details/121/69/0/0 Solar Panels – SunnyTech 120W x 4...
diysolarforum.com diysolarforum.com

I do not know what size breakers/fuses to use, and if I have enough or if I have too many - thoughts?

The solar needs both cables to "break" or disconnect, other just the one

The battery fuse is important and should be rated for max system

Each time you change the spec of a wire you should fuse for that wire.

Where would grounding wires go in the diagram?
"Grounding" in vehicles can be a confusing term, its different from "earth" in a domestic set up. In a vehicle its typically used as the return path -ve back to the battery completing the circuit which uses less wire and can make things simpler. Getting a good connection through a modern van can be problematic though.

Any other feedback/comments/concerns with this setup?
Check the specs of the SCC youve shown, its solar input is limited plus your batteries aren't in balance with your panels ability to charge them.
You need to be aiming to recharge your batteries each "average' day (can be difficult in the winter)
 
rmaddy said:
You have 7,680Wh of battery but only 300W of solar. It would take over 25 hours of perfect solar conditions to fully recharge your batteries. Given that your panels will likely be flat mounted on the roof then it will take even longer. The fact that you can charge via the alternator does help offset this mismatch.

Do you really need a 3000W inverter? What do you plan to run on AC that requires so much power?
Click to expand...
We're targeting no less than 600W of solar for our system. The image doesn't quite note that well enough, that's my fault.

I was reading that a lot of induction cooktops require 1800W of power to use, and if we were to use that for an extended period of time the inverter would need to be a bit larger than 2000W. Also, if we wanted to run the induction cooktop and a oven at the same time, that'd also increase the watt usage over 2000W
 
mikefitz said:
Breakers or fuses for over current protection are only needed in the positive paths.

In a metal body van the 'ground' is the van metalwork

The decision for a 12 or 24 volt system rests usually of how much power you will be using with the inverter. Although you show a 3000 watt inverter, just how much AC load do you expect to need?

Your diagram and parts identified are for a 12v system with the batteries wired in parallel, the Renogy dc to dc and MPPT charger is only usable for a 12 volt system with maximum of about 400 watts of panels.

If you decide on a 24 volt system you will need the panels configured to give a higher voltage to the solar charger.

With a 24 volt system the batteries will be in series so you will need a 24 to 12 Dc to Dc converter for the 12v dc appliances.

A 24 volt inverter for 3000 watt loads is practical, if the actual power needed is lower then a 1500 watt inverter is usable on a 12v system.

I suggest before proceeding, evaluate your actual need for 3000 watts of AC power.. If you need the 3000 watts then a 24 volt system is more practical. However this needs more parts, a DC to DC, 24 to 12, and a different solar controller, panel configuration and engine DC charger.

With the inverter and a permanent install with distributed AC wiring and multiple appliances and outlets there is a risk of electric shock. A earth leakage protection device is needed and to ensure this will operate correctly the inverter needs a neutral to protective earth bond at the inverter. The inverter installation literature should have details. The AC protective earth connects to van 'ground'.

You may wish to consider an inverter charger. This has auto switching between shore and battery power for the AC system, makes things easier for the AC side and looks after the neutral bond


Mike
Click to expand...
Thanks Mike - I am going to take your feedback and create a more details diagram and repost when I can :). In regards to the 3000W inverter, I was read that a lot of induction cooktops require 1800W of power to use, and if we were to use that for an extended period of time the inverter would need to be a bit larger than 2000W. Also, if we wanted to run the induction cooktop and a oven at the same time, that'd also increase the watt usage over 2000W.
 
ianganderton said:
Should this be a 12V system or a 24V system?

Most of your items are DC and the inverter is 3000W which is on the cusp of whats viable/sensible for 12V. I have similar use but a 2000W inverter and I'm going 12V

diysolarforum.com

My Build Questions - Camper Van 480W Solar 12V 200Ah LifePo4

Finally starting to install this system Purchased Product Specifications Battery – SunnyTech (badged Lithium Valley) 12V 200Ah Lifepo4 https://web.archive.org/web/20210130064931/https://sunnytech.co.nz/store/default/product-details/121/69/0/0 Solar Panels – SunnyTech 120W x 4...
diysolarforum.com diysolarforum.com

I do not know what size breakers/fuses to use, and if I have enough or if I have too many - thoughts?

The solar needs both cables to "break" or disconnect, other just the one

The battery fuse is important and should be rated for max system

Each time you change the spec of a wire you should fuse for that wire.

Where would grounding wires go in the diagram?
"Grounding" in vehicles can be a confusing term, its different from "earth" in a domestic set up. In a vehicle its typically used as the return path -ve back to the battery completing the circuit which uses less wire and can make things simpler. Getting a good connection through a modern van can be problematic though.

Any other feedback/comments/concerns with this setup?
Check the specs of the SCC youve shown, its solar input is limited plus your batteries aren't in balance with your panels ability to charge them.
You need to be aiming to recharge your batteries each "average' day (can be difficult in the winter)
Click to expand...
Great feedback - I am going to create a new diagram and repost when I can.
 
600W x 5 (average hours of solar hours) = 3000W back into the batteries, you will need to double the solar to get value from those batteries

Bear in mind that 5 x solar hours is a global year round average. Where are you?
 
ianganderton said:
600W x 5 (average hours of solar hours) = 3000W back into the batteries, you will need to double the solar to get value from those batteries

Bear in mind that 5 x solar hours is a global year round average. Where are you?
Click to expand...
Good to know. We will have shore and an alternator running as well, which will help put power back into the batteries.

We are in the US and will most likely be traveling weather patterns for best seasons.
 
clammchops said:
We're targeting no less than 600W of solar for our system.
Click to expand...
600W is better but keep in mind that still means it can take at least 14 solar hours to fully recharge your batteries.

clammchops said:
Also, if we wanted to run the induction cooktop and a oven at the same time, that'd also increase the watt usage over 2000W.
Click to expand...
What kind of oven?

Let's say you use the cooktop and the oven and they use 2500W. Let's say while making a meal you need to run both for 20 minutes. That's a bit over 830Wh. It will take your 600W of solar anywhere from 90 minutes to 8 hours (depending on the sun) to recharge the battery just from 20 minutes of cooking. Something to keep in mind.
 
clammchops said:
Good to know. We will have shore and an alternator running as well, which will help put power back into the batteries.

We are in the US and will most likely be traveling weather patterns for best seasons.
Click to expand...
With the solar charge controller your speced you'll charge at 30A whether its solar or alternator, its not 30+30

30A @ 12V = 360W per hour max

If you are heading into the world of induction cooking you are going to need a very very hi speced system that optimises all charging inputs and you will struggle to find numbers that work for a van despite what some youtube videos will have you believe. Induction can be done but its expensive so its definitely worth considering propane for cooking , heating and water heating duites, there is a hell of a lot of watts stored in a bottle of gas
 
Since you are depending on your power in a van, I would make the following changes.

A 30a mppt controller will only handle 440watts of solar. You may want to consider two 100/30 or a 100/50. I would recommend looking at the Victron mppt’s. You may also want to add an extra mppt and use some portable panels on the ground. Many Vans have extreme difficulty getting enough solar on the roof. If possible design your panels so they can tilt. (This week in Arizona my 420w array got a Pv max of 345 watts when tiled - Flat (because of wind) the Pv max was 258w - that adds up over a day).

I would use a Victron Orion smart dc-dc non-isolated charger. This way when you are driving you get 30amps plus your solar. You will not need the breakers- just a 30amp fuse on both power wires. You can turn it on/off with either a switch or via your Bluetooth phone.

You have chosen the Victron BMV712 for a shunt, Unless you need the display, I would recommend the Smartshunt - it saves you like $70 or so.

The reason for going all Victron is many of the items will communicate- the Smartshunt will send voltage,current, and temperature to the mppt’s. Also, take a look at YouTube on the Cerbo and touch. They are expensive but having the data all in one place of what is happening to your system can be priceless. Also, they can help find problems by giving data on the system. You can also roll your own Cerbo with a Raspberry Pi.

The Victron Smartshunt (or BMV712) and the smart mppt’s you can access and change and program on Bluetooth from your phone.

Batteries- what size of bms does those batteries have? How much current can the bms’s deliver? To run a 3000watt inverter on 12v - the Victron manual wants 400amp fuses. It may be better to go with a 2000w inverter/charger and only use one high power item at a time. (Oven first - then induction).

The Victron 2000w inverter will deliver 1600 watts - would that be enough if you don’t run the induction plate on high? I never cook with the induction over a medium. (This is why you need to take a very close look at each items data sheet and manual before you buy - many times things get marketed differently than the actual specs). - I still don’t understand how VA is a substitute for watts…

You currently have both an inverter and a charger in your system - look at a Multiplus 2000 or 3000. They are expensive- but really good. They are also pure sign wave - electronics like sign wave.

Shore power 50amp is way too much for your rig. You only need 15 amp (although for that wire run use 10g Wired directly to the Multiplus. That way you can safely use a 30a to 15a dogbone for those times you stay in a RV park that has 30a.
 
Rocketman said:
Since you are depending on your power in a van, I would make the following changes.

A 30a mppt controller will only handle 440watts of solar. You may want to consider two 100/30 or a 100/50. I would recommend looking at the Victron mppt’s. You may also want to add an extra mppt and use some portable panels on the ground. Many Vans have extreme difficulty getting enough solar on the roof. If possible design your panels so they can tilt. (This week in Arizona my 420w array got a Pv max of 345 watts when tiled - Flat (because of wind) the Pv max was 258w - that adds up over a day).

I would use a Victron Orion smart dc-dc non-isolated charger. This way when you are driving you get 30amps plus your solar. You will not need the breakers- just a 30amp fuse on both power wires. You can turn it on/off with either a switch or via your Bluetooth phone.

You have chosen the Victron BMV712 for a shunt, Unless you need the display, I would recommend the Smartshunt - it saves you like $70 or so.

The reason for going all Victron is many of the items will communicate- the Smartshunt will send voltage,current, and temperature to the mppt’s. Also, take a look at YouTube on the Cerbo and touch. They are expensive but having the data all in one place of what is happening to your system can be priceless. Also, they can help find problems by giving data on the system. You can also roll your own Cerbo with a Raspberry Pi.

The Victron Smartshunt (or BMV712) and the smart mppt’s you can access and change and program on Bluetooth from your phone.

Batteries- what size of bms does those batteries have? How much current can the bms’s deliver? To run a 3000watt inverter on 12v - the Victron manual wants 400amp fuses. It may be better to go with a 2000w inverter/charger and only use one high power item at a time. (Oven first - then induction).

The Victron 2000w inverter will deliver 1600 watts - would that be enough if you don’t run the induction plate on high? I never cook with the induction over a medium. (This is why you need to take a very close look at each items data sheet and manual before you buy - many times things get marketed differently than the actual specs). - I still don’t understand how VA is a substitute for watts…

You currently have both an inverter and a charger in your system - look at a Multiplus 2000 or 3000. They are expensive- but really good. They are also pure sign wave - electronics like sign wave.

Shore power 50amp is way too much for your rig. You only need 15 amp (although for that wire run use 10g Wired directly to the Multiplus. That way you can safely use a 30a to 15a dogbone for those times you stay in a RV park that has 30a.
Click to expand...
Okay - I have made a second draft and edited it in the original post. I am curious on your thoughts :). I've also provided a list of stuff in the diagram, as well as some questions.
 
Last edited:
ianganderton said:
With the solar charge controller your speced you'll charge at 30A whether its solar or alternator, its not 30+30

30A @ 12V = 360W per hour max

If you are heading into the world of induction cooking you are going to need a very very hi speced system that optimises all charging inputs and you will struggle to find numbers that work for a van despite what some youtube videos will have you believe. Induction can be done but its expensive so its definitely worth considering propane for cooking , heating and water heating duites, there is a hell of a lot of watts stored in a bottle of gas
Click to expand...
Okay - I have made a second draft and edited it in the original post. I am curious on your thoughts :). I've also provided a list of stuff in the diagram, as well as some questions.
 
rmaddy said:
600W is better but keep in mind that still means it can take at least 14 solar hours to fully recharge your batteries.


What kind of oven?

Let's say you use the cooktop and the oven and they use 2500W. Let's say while making a meal you need to run both for 20 minutes. That's a bit over 830Wh. It will take your 600W of solar anywhere from 90 minutes to 8 hours (depending on the sun) to recharge the battery just from 20 minutes of cooking. Something to keep in mind.
Click to expand...
Okay - I have made a second draft and edited it in the original post. I am curious on your thoughts :). I've also provided a list of stuff in the diagram, as well as some questions.
 
mikefitz said:
Breakers or fuses for over current protection are only needed in the positive paths.

In a metal body van the 'ground' is the van metalwork

The decision for a 12 or 24 volt system rests usually of how much power you will be using with the inverter. Although you show a 3000 watt inverter, just how much AC load do you expect to need?

Your diagram and parts identified are for a 12v system with the batteries wired in parallel, the Renogy dc to dc and MPPT charger is only usable for a 12 volt system with maximum of about 400 watts of panels.

If you decide on a 24 volt system you will need the panels configured to give a higher voltage to the solar charger.

With a 24 volt system the batteries will be in series so you will need a 24 to 12 Dc to Dc converter for the 12v dc appliances.

A 24 volt inverter for 3000 watt loads is practical, if the actual power needed is lower then a 1500 watt inverter is usable on a 12v system.

I suggest before proceeding, evaluate your actual need for 3000 watts of AC power.. If you need the 3000 watts then a 24 volt system is more practical. However this needs more parts, a DC to DC, 24 to 12, and a different solar controller, panel configuration and engine DC charger.

With the inverter and a permanent install with distributed AC wiring and multiple appliances and outlets there is a risk of electric shock. A earth leakage protection device is needed and to ensure this will operate correctly the inverter needs a neutral to protective earth bond at the inverter. The inverter installation literature should have details. The AC protective earth connects to van 'ground'.

You may wish to consider an inverter charger. This has auto switching between shore and battery power for the AC system, makes things easier for the AC side and looks after the neutral bond


Mike
Click to expand...
Okay - I have made a second draft and edited it in the original post. I am curious on your thoughts :). I've also provided a list of stuff in the diagram, as well as some questions.
 
clammchops said:
  • Solar:
    • Do I wire in Series or Parallel?
Click to expand...
the panels are high voltage around 70 volts, wire in parallel.
clammchops said:
Is a 50A breaker sufficient for the solar?
Click to expand...
2 panels will deliver 12 amps, 3 panels in parallel 18 amps, fuse each string 15 amps before the parallel connection. Use a DC isolator, solar specification for solar disconnect.
clammchops said:
  • Alternator:
    • Is the 30A breaker correct,
Click to expand...
For a Victron 12 12 30 protection is suggested, see instructions, at 50 amps, use a fuse 50A at starter battery and service battery main buss bar
clammchops said:
  • Batteries:
    • Should these be wired in series or parallel?
Click to expand...
Series for a 24 volt system, parallel for a 12 volt system. From your comments it seems you want a 12v system.
clammchops said:
How would you add a 30A fuse on both power wires?
Click to expand...
fuses or breakers only on positive cables.
 
Here are the little changes and notes for your second drawing.

4/0 wiring - you need 4/0 wires from your batteries through the power in and to the inverter. (Currently you have 2/0 wires from batteries to Power In). Also verify your Safety switch can handle the massive amps (some cannot).

Batteries- did you check the bms ratings of those batteries to make sure they can discharge enough power to power the inverter- is the bms a 100a discharge or 150a or 200a discharge? This is very important to match up otherwise your inverter will not get enough power. Depending on the bms you may be better with three batteries of 200ah than two batteries of 300ah.

Smartshunt- does not have a display on it you use Bluetooth on your phone - the display was for BMV712.

Solar Panels - your solar panels say a Voc of 69v - these MUST be hooked up in parallel to a mppt of 100/50. (Your currently show a serial wiring). If wired in series the Voc adds so you will put 140v into a mppt that can only handle 100v and you will fry it immediately. The breaker between the panels and the mppt is just to turn the sun off 20a will be fine.

Look on YouTube for a video how to add fuses to the Power In. That way all wires will have fuses.

You won’t need the copper bars just before the power in.

You have a 400a Mega fuse on the battery positive- if you want to keep the fuse holder change to a class T. Those two batteries will be paralleled.

Research item: there are a couple of ways of controlling the Multiplus (on/off and changing the power input from shore). Cerbo(or other GX device, a DSU (basic panel), or on phone with a Bluetooth dongle. Find the one that works best for you - like above I would use the Cerbo for all the other info you get…

For the dc-dc charger from the alternator- you probably want a fuse instead of a breaker. (Smaller, cheaper).

It is looking good!
 
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