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RV All-in One Diagram ready for critique

eXodus

Solar Addict
Joined
Jul 27, 2020
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This came out of the replies I got from my initial thread:

Please take a look and let me know if I miss sized wires or fuses before I go on a shopping spree :p

All In One RV System.png
 
@eXodus your drawing makes it look like the Growatt has dc "load" lugs?
Does it?
Anyway the wire to the dc load center needs over current protection.
Urge you stick with a reputable name brand breaker.
I don't consider t-tocas to be a reputable name brand.

Is the legacy system properly wired and fused?
 
@eXodus your drawing makes it look like the Growatt has dc "load" lugs?
Does it?
there are no 24V "loads" in my system planned. Only the Growatt connects to the 24v batteries.

Urge you stick with a reputable name brand breaker.
I don't consider t-tocas to be a reputable name brand.
I'd be happy to hear suggestions. Not settle on that one.

Same for the inline fuses - wanted to take Renogy.

Is the legacy system properly wired and fused?
the existing system is in the RV for 16 years from the factory, didn't burn up till now. It's 30A powercenter with a 45A WFCO. Converter Charger.
The only thing I added was the solar panel + the PWM.
The PWM has a 10A Fuse on a 12 gauge wire. I can add that to the picture.

Thanks for taking the time!
 
This came out of the replies I got from my initial thread:

Please take a look and let me know if I miss sized wires or fuses before I go on a shopping spree :p

View attachment 63145
The 30a fuse on your solar panel wire is what I have seen suggested and some say, you need to put a breaker on both lines based on NEC or something. The key to having a breaker vs a fuse is the ability to disconnect the incoming power.
 
there are no 24V "loads" in my system planned. Only the Growatt connects to the 24v batteries.
I see now, the only connection between new system and the legacy system is ac.
I'd be happy to hear suggestions. Not settle on that one.

Same for the inline fuses - wanted to take Renogy.

Waytek has a good reputation for selling quality products.
All the circuit breaker brands below that link should be fine.
I doubt you will find any dodgy fuses there either.
 
The key to having a breaker vs a fuse is the ability to disconnect the incoming power.
that would be valid reason to have a breaker,
Otherwise I think MC4 are not that difficult to unplug. Wanted to have the inline fuse underneath the Growatt. I don't think NEC applies in a DC setup in an RV - residential install - yes. Could be wrong.

Waytek has a good reputation for selling quality products.
All the circuit breaker brands below that link should be fine.
thanks! Will look into those.

I see now, the only connection between new system and the legacy system is ac.

Correct AC coupled only between the old stuff (12V lead) and the new 24V LFP.

I just don't want the headache of DC-DC conversion equipment. Way to expensive and doesn't have much power - and my 12V is working perfectly fine.
 
that would be valid reason to have a breaker,
Otherwise I think MC4 are not that difficult to unplug. Wanted to have the inline fuse underneath the Growatt. I don't think NEC applies in a DC setup in an RV - residential install - yes. Could be wrong.
In my case, the MC4 is on the roof with the panels and the SCC is under a bed where everything else is. I go from PV cable with a ferrule to the SCC. So you would need a tool to disconnect vs. just flipping a pair of switches.
 
Waytek has a good reputation for selling quality products.
All the circuit breaker brands below that link should be fine.
All In One RV System  V2.png

Just updated the diagram with your suggested breaker and added a few more descriptive elements which I noticed from comments where unclear. AC - coupling between Growatt and 12V legacy system
 
In my case, the MC4 is on the roof with the panels and the SCC is under a bed where everything else is. I go from PV cable with a ferrule to the SCC. So you would need a tool to disconnect vs. just flipping a pair of switches.
how often do you have to disconnect your solar panels? On the last Van (200w, 450Ah 12V lead) I built with solar 5 years ago - I disconnected the solar panel once from SCC - when I changed the batteries. I usually just have pigtails about a foot in length MC4 connectors dangling right below the controller. - just got a 2 ft MC4 extension - cut it in the middle - two pigtails. My idea was that I can change the SCC quickly in case it fails.

I don't foresee that I need to disconnect the panels very often.
 
Those batteries can't supply the current to power that all_in_one at full draw.
3000 ac watts / .85 conversion factor / 12 volts low cutoff = 147.058823529 service amps
 
you got a 30A double DC breaker you can recommend?
I got this idea from the Explorist, used his idea, passing it along:

2P 250V Low-voltage DC Miniature Circuit Breaker For Solar Panels Grid System din rail mount(32A)

For my application, 32A, but they have 16 and 63a also.

Then, to keep them from being accidentally bumped, they go in one of these.
Circuit Breaker Distribution Box, Outdoor Waterproof Distribution Box Breaker for 5 WAYS Circuit Breaker Indoor on The Wall

The box holds 4 breakers which is nice as I will have two separate solar panel strings so all four cables can go through here on the way to the SCCs.
 
My mistake.
Should be good.
thanks or checking my math anyhow :)

The like you said the growatt should pull about 150A max - According to manual they even state 163A
So the batteries with 200A should be fine.

The largest load I got on the system is my 1100w A/C unit - (softstart) I hope the the 3000w Growatt is able to handle that.
I usually only need about 2kwh through the night.
For my application, 32A, but they have 16 and 63a also.
the 30A inline fuse is $15 - the 32A double breaker is $23 makes it interesting product since it's disconnecting both wires of the solar system
Then, to keep them from being accidentally bumped
I'm not sure if I got the space for a box to protect the breaker. That makes it less attractive then the inline fuse.
 
thanks or checking my math anyhow :)

The like you said the growatt should pull about 150A max - According to manual they even state 163A
So the batteries with 200A should be fine.

The largest load I got on the system is my 1100w A/C unit - (softstart) I hope the the 3000w Growatt is able to handle that.
I usually only need about 2kwh through the night.

the 30A inline fuse is $15 - the 32A double breaker is $23 makes it interesting product since it's disconnecting both wires of the solar system

I'm not sure if I got the space for a box to protect the breaker. That makes it less attractive then the inline fuse.
you don't need the box. They mount on DIN rail You just need a piece of DIN rail the width of the breakers that you attach to the wall and clip the breakers on. The box is just for klutz's like me.
 
System PartsQuantity:Price/ UnitTotalLink
Ampere Time 24V 100Ah2$870.00$1,740.00https://www.amazon.com/gp/product/B08P6LP1J9/
Growatt 24V SPF 3000TL LVM1$750.00$750.00https://watts247.com/product/spf-3000tl-lvm-24p/?wpam_id=3
Solar Panel 435W3$150.00$450.00Local Pickup
Solar Panel Mounts6$24.00$144.00https://www.amazon.com/gp/product/B08HLH58L1
200A Breaker1$45.00$45.00https://www.waytekwire.com/item/46875/EATON-s-Bussmann-Series-187200F-03-1-Marine-Rated/
M8 Lugs and Shrink1$11.00$11.00https://www.amazon.com/gp/product/B092ZM1ZG2/
10Ft 2AWG Wire1$32.00$32.00https://www.amazon.com/gp/product/B017GB470O/
30A Inline Fuse MC41$13.00$13.00https://www.amazon.com/PowMr-M-C-4-Waterproof-Holder-Connector/dp/B08C2K2NMQ/
15A Inline Fuse MC43$12.00$36.00https://www.amazon.com/PowMr-M-C-4-Waterproof-Holder-Connector/dp/B08C26GJGQ/
3 to 1 Branch MC42$13.00$26.00https://www.amazon.com/Renogy-Solar-MC4Y2-Branch-Connectors/dp/B01NH0BWV9/
30 FT 10 AWG MC41$45.00$45.00https://www.amazon.com/BougeRV-Extension-Female-Connector-Adaptor/dp/B075424L8R/
Solar Wire Entry Gland1$12.00$12.00https://www.amazon.com/Link-Solar-Weatherproof-Project-Campervan/dp/B0111RNZDY
50FT 30 AMP RV Cable1$90.00$90.00https://www.amazon.com/RVGUARD-Extension-Indicator-Organizer-Standard/dp/B085HLWSTL
Random Stuff Buffer$200Sealant, wire mounts etc.
Grand Total$3,594.00


Putting everything together in a table. I can probably get some items cheaper when I shop around or use some affiliate links etc.
 
Those bats are cheaper than a Battle Born, but way more expensive vs. a DIY battery. If I hadn't built my own battery banks, I would never have been able to afford the solar system. I used breakers on my solar panels vs. fuses as the breakers allow me to turn off the solar if needed for testing or working on the system.
 
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