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

Abodyofscience

Solar Enthusiast
Joined
Feb 21, 2022
Messages
168
24v vs 12v needs half the current so saves on copper but this cost saving is probably swamped out by the total system cost.

300w on 20% of the time = 3000w on 2% of the time with no batt. charge or discharge.
 

Rocketman

Solar Addict
Joined
Sep 27, 2020
Messages
720
I just saw your questions under your new drawing:
Solar
1.panels Must be parallel!!!
2. 20a is good - this is mainly a switch to turn the sun off - for various maintenance reasons.
3. A 3rd panel would be over paneled for the 100/50. It can only pass along 700watts - it will clip anything above that. If you add a 3rd panel add an additional mppt - 100/20 or 100/30 just for that panel. If you decide a 3rd panel will fit you could change the mppt 100/50 to a 150/60. The panels would still need to be in parallel and you would need to add fuses to the panels (they make a MC4 inline fuse).

Alternator- 30a fuse. For this fuse a automotive 30a fuse with 10 or 8 gauge wire is fine.

Shore: 👍 all good there.

Instead of the Lynx Distributor- get the Lynx Power In and look for a YouTube to add the fuses it to (this turns it into a distributor except for the electronic module and led lights for blown fuses). This will let you have each wire that leaves the Lynx have a fuse. (That is a most excellent thing!)

For the battery monitor (shunt) you will use either a Smartshunt or a BMV712. The Smartshunt is cheaper because it doesn’t have the extra display. (I would use the Smartshunt).

To get the data to the Cerbo you will need 2 VE.Direct cables. One from the mppt and one from the Smartshunt. You will also need a network cable from the Multiplus to the Cerbo. These data cables will allow for the communications. (The Dc-dc charger will not connect to the Cerbo). If you add another mppt - just add the data cable too. The touch just attaches to the Cerbo with its included cable. It is really easy to get the Cerbo up and running.

Don’t just order the Victron stuff from Amazon. Find a Victron dealer and talk to them - give them your plans… They can help you when you run into difficulties and questions. My Victron dealer is https://www.continuousresources.com/
He ships everywhere.
 

clammchops

New Member
Joined
Feb 22, 2022
Messages
18
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).
Okay it sounds like I need larger wire - better to be safe than sorry! The switch I put in was just a placeholder - if you have any recommendations on switches that'd handle the load that'd be great!

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.
I am using 2x 300AH Epic Lithium Batteries that each have a built in 150A Smart BMS. The local manufacturer only makes them in 300AH lots and I was hoping to source locally. Would these batteries work?

Smartshunt- does not have a display on it you use Bluetooth on your phone - the display was for BMV712.
Good to know - so no need for the battery monitor device.

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.
Oops, yes - I meant to wire these in parallel for that reason + not limiting the array due to shaded areas.

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.
Sounds like I can get rid of the copper bars and just add fuses in-line. Are there specific sized fuses I'd need?

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.
Sorry - I am very new to all of this - what is a class T? I assume it's something that'd be safer for the 12V 600AH Lithium batteries, but not sure :)

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…
How would the Cerbo GX wire up to this system? What about if I wanted to add a GX Touch to the mix as well?

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

Rocketman

Solar Addict
Joined
Sep 27, 2020
Messages
720
Okay it sounds like I need larger wire - better to be safe than sorry! The switch I put in was just a placeholder - if you have any recommendations on switches that'd handle the load that'd be great!
Blue sea makes good but expensive switches - there may be others that are cheaper.
I am using 2x 300AH Epic Lithium Batteries that each have a built in 150A Smart BMS. The local manufacturer only makes them in 300AH lots and I was hoping to source locally. Would these batteries work?
That’s 300a at full (which you probably won’t do often - so I would say it would work.
Good to know - so no need for the battery monitor device.
Yes you want a Smartshunt (which is a battery monitor) - you probably do not need the display . Especially if you get the Cerbo - the touch will be the display.
Oops, yes - I meant to wire these in parallel for that reason + not limiting the array due to shaded areas.


Sounds like I can get rid of the copper bars and just add fuses in-line. Are there specific sized fuses I'd need?
You match the fuses to the wire. So the 4/0 wires to the battery and inverter will have 300a (or 400a) fuses, the 6ga wires to the mppt probably a 60a and if you use the same 6ga wire for the Dc-Dc use a 60a as well - (that wire could be 8awg or 10 awg with a 30 or 40a fuse - but it may be easier to use 6 wire and 60a fuses for it. (Less different parts - but it might cost more for no real benefit).
Sorry - I am very new to all of this - what is a class T? I assume it's something that'd be safer for the 12V 600AH Lithium batteries, but not sure :)
How close will your batteries be to the Lynx Power In? How many feet of 4/0 wire? You will have a fuse at the Power In, if it’s a long run you will need a fuse at the battery too. Class T fuses are the best but very expensive.

How would the Cerbo GX wire up to this system? What about if I wanted to add a GX Touch to the mix as well?


Sweet, love it!
 

clammchops

New Member
Joined
Feb 22, 2022
Messages
18
24v vs 12v needs half the current so saves on copper but this cost saving is probably swamped out by the total system cost.

300w on 20% of the time = 3000w on 2% of the time with no batt. charge or discharge.
Could you explain more on what you mean?
 

Abodyofscience

Solar Enthusiast
Joined
Feb 21, 2022
Messages
168
Could you explain more on what you mean?
Sorry for the lack of details & I see I made some mistakes.

As in house maximum & average energy requirements, there is demand factor and diversity factor as defined in the NEC.
For example, our house uses 24 kw max [virtually never] and 1 kW average, even though we have 200A [48 kw] service.

Now on to your specifics, somewhere in here I thought I saw 300w but now it seems your power source is 330 x 2 = 660w.
So, 660w on for 5 hrs of full sun [21% of 24 hours] is 3,300 watt-hours.
Assuming perfect energy storage, you could have a 3,300 watt load on for 1 hour, 4% of 24 hours.
With imperfect storage you’d get less power for 1 hour or more power for less than 1 hour.

I can’t do the finer points of solar but I hope I can find some of the limits of what’s practically possible, using my spreadsheet [posted in another thread].

Determining the optimum design center value
[most kw for least $ for longest service lifetime]
for a system like this is beyond me, but this forum provides good practice & rules for zeroing in on an optimum.

Thanks for asking. :)
 

12VoltInstalls

…myself everything do I…
Joined
Jan 18, 2021
Messages
4,033
Location
Vermont
Are you totally committed to an induction cookplate? You have a significant amount of “over kill” designed in to accommodate <5% time of use.

A single or two-burner RV “range” is about the same to half the cost of basic induction tops- or 75% less than the “nice” induction tops. So no biggie there. However, years of propane cooking is more versatile and cheaper than the extra cost you’ll be incurring to accommodate an induction plate.
I personally wouldn’t go that direction- your system without the induction cooker is robust. I think it will very much exceed your needs by the looks - minus the big-amp cooker.

In my case I’m running a small ‘house’ with WAY less equipment and cost. I’m utilizing a camper with a number of mods for full-time living. 25’ and essentially ‘stationary,’ though remaining towable at any time.

In summer I can support a 120V fridge and all the ‘normal’ electrical needs with as little as 400W of panels (I have 800 running now). The overhead for supporting my cooking with electric would be huge- but the magic chef propane RV range is quick, flexible, and inexpensive to feed. Baking a pie, cooking a roast, frying breakfast sausage…no solar hit.

For camping I’d ditch the induction cooker idea in a heartbeat and just make it work with propane. $20 of propane likely would last the entire spring through fall.

Second thought is an aio unit. I’m not a fan of aio systems EXCEPT the costs are so low and even some budget-friendly brands have years of dependable service for people. The field is secure, costs low, and simplicity enviable- plus they’ll handle shorepower or generator input and charging automatically.

Just some thoughts from a frugal northeastern US perspective.
 

gelmjw

Solar Enthusiast
Joined
Nov 19, 2019
Messages
125
Location
Oklahoma
I have two suggestions for INVERTER based 120ACV appliances which I have run on a 1000W inverter for years. On this type of appliance, the power level controls the Wattage draw.

In contrast, a regular 1800W capable appliance switches full power on/off. In the on/off case, an 1800W appliance will alternate from zero to 1800W. Obviously my 1000W inverter cannot power that.

Another advantage of an inverter appliance is that the generator will run at a steady speed. Otherwise, the eco mode may not work when the genny needs to speed up from idle repeatedly.

1. Inverter microwave. Panasonic makes an inverter model that I know works on under 1000W on power levels 1-5.

2. Inverter-Induction cooktop. I have a portable one that makes a grilled cheese sandwich at the 400W setting. At 900W I can boil soup. The brand is Rosewill.

Do you still need more than a 1000W inverter?
 
Last edited:

ianganderton

Auckland, NZ
Joined
Nov 8, 2019
Messages
567
Location
Auckland, New Zealand
Second thought is an aio unit. I’m not a fan of aio systems EXCEPT the costs are so low and even some budget-friendly brands have years of dependable service for people. The field is secure, costs low, and simplicity enviable- plus they’ll handle shorepower or generator input and charging automatically.

Just some thoughts from a frugal northeastern US perspective.

Only thing to check with the All In One units is they sometimes have noisey fans that run a lot which can be an annoying problem in a close quarters camper-van environment.
 

jberger

Solar Addict
Joined
Jun 1, 2021
Messages
272
FWIW, We love having induction cooking in our RV and Home.
We didn't want ANY propane in our current coach, so we have a residential fridge, induction cooktop, etc. It does mean we have to have bigger inverters and battery bank, but I'd never go back to propane.
I've watched a couple of RV's burn due to propane fires and I just don't want to put my family in there with Propane. Our last RV was full propane (even the genset) but we chose not to go that way this time around.
 

clammchops

New Member
Joined
Feb 22, 2022
Messages
18
Blue sea makes good but expensive switches - there may be others that are cheaper.

That’s 300a at full (which you probably won’t do often - so I would say it would work.

Yes you want a Smartshunt (which is a battery monitor) - you probably do not need the display . Especially if you get the Cerbo - the touch will be the display.

You match the fuses to the wire. So the 4/0 wires to the battery and inverter will have 300a (or 400a) fuses, the 6ga wires to the mppt probably a 60a and if you use the same 6ga wire for the Dc-Dc use a 60a as well - (that wire could be 8awg or 10 awg with a 30 or 40a fuse - but it may be easier to use 6 wire and 60a fuses for it. (Less different parts - but it might cost more for no real benefit).

How close will your batteries be to the Lynx Power In? How many feet of 4/0 wire? You will have a fuse at the Power In, if it’s a long run you will need a fuse at the battery too. Class T fuses are the best but very expensive.
Hey there! I've been out of town and haven't had time to revisit this until now. We've decided to change our solar array to have the following: 3x 200W solar panels (link below). I made a few changes but before purchasing any parts, I was looking to see if you have any input regarding proper safety/wiring with what the new diagram looks like.

Additionally, would this setup work if we purchased a fourth solar panel and wired it in series-parallel?


Solar panels: https://www.newpowa.com/collections/rigid-solar-panels/products/new-200w-mono-12v-solar-panel
 

Attachments

  • electrical_new_600WSolar.png
    electrical_new_600WSolar.png
    593.1 KB · Views: 14

Rocketman

Solar Addict
Joined
Sep 27, 2020
Messages
720
Yes four 200watt panels in 2s2p will be fine. If you wire three panels in parallel they each need a 15a fuse. There are MP4 connectors that have fuses in them. If 3s or 2s2p don’t need those fuses.

Here are a couple little things.

You have a fuse between panels and SCC - this is just to turn the sun off for maintenance. You may want to look at a breaker there (easier to use).
You also have fuses on both the positive and negative wires going to the batteries - Positive- definitely - Negative- I don’t think that’s a good idea. I think you only want to fuse the positive (I am not sure where I got that idea - so maybe someone else will know)

Looks great!
 

Rocketman

Solar Addict
Joined
Sep 27, 2020
Messages
720
Oh one more little thing…
From the inverter you have 4/0 - positive and negative- but you also have a 2/0 ground. I don’t think you need that large of a ground wire (read the install manual) plus I would take it to the frame ground.
 

12VoltInstalls

…myself everything do I…
Joined
Jan 18, 2021
Messages
4,033
Location
Vermont
would this setup work if we purchased a fourth solar panel and wired it in series-paralle
It’s late and I did not evaluate your drawing but have a comment. I would not purchase a prime number of panels and would try not to buy a number not divisible by 2 or 4. (9 panels with 3S3P could take 3 more panels with options)
Buy the 4th panel! :)
 

clammchops

New Member
Joined
Feb 22, 2022
Messages
18
It’s late and I did not evaluate your drawing but have a comment. I would not purchase a prime number of panels and would try not to buy a number not divisible by 2 or 4. (9 panels with 3S3P could take 3 more panels with options)
Buy the 4th panel! :)
We're going to try to stay at 3 panels for now to save some space on our roof. Is there a reason why we should not have 3 panels? We did purchase a Y branch connector that can combine 3 panels in parallel (both M/FFF and F/MMM).
 

12VoltInstalls

…myself everything do I…
Joined
Jan 18, 2021
Messages
4,033
Location
Vermont
Is there a reason why we should not have 3 panels?
Not a reason not to.

Just that series-parallel arrays need to be balanced to work out - not super critical at 3 panels I guess cuz you can buy one later and have 4S or 2S2P. I just think adding panels increases usefulness. When I went to 400W from 300W it was rounding a corner for me- it was not “1/3 more” it just became way usable with series panels compared to parallel (lower voltage).

Give 3 a shot. It may work but you know what to do if it doesn’t.
 

clammchops

New Member
Joined
Feb 22, 2022
Messages
18
Not a reason not to.

Just that series-parallel arrays need to be balanced to work out - not super critical at 3 panels I guess cuz you can buy one later and have 4S or 2S2P. I just think adding panels increases usefulness. When I went to 400W from 300W it was rounding a corner for me- it was not “1/3 more” it just became way usable with series panels compared to parallel (lower voltage).

Give 3 a shot. It may work but you know what to do if it doesn’t.
Haha okay that makes sense. Yeah I think we'll plan on 3 if there are no safety concerns :D. If we don't get enough juice, we'll upgrade the MPPT and put a 4th panel on haha. Speaking of MPPT, the 100/50 should work for 3 panels - but would it work for 4 panels?
 

Rocketman

Solar Addict
Joined
Sep 27, 2020
Messages
720
Yes it will work for four in a 2s2p setup. It does have a max of 700watts @12v (everything above that will just be clipped). But the big advantage is all the additional watts when not in ideal conditions. I only noticed the clipping once on my rig (four flat -mounted 200w panels).
 
Top