My diagram for my 600W DIY LiFePO4 van mounted system (First Solar System!)

[elpulpo]

Hey DIY Solar Power Forum, really excited to be working on the designs for my first ever solar build. I designed this build to power my office and living space in my 1990s Toyta Hiace. The van is still on its way from Japan and I've already ordered the batteries (Lishen) from Alibaba. Have a look at my diagram and please let me know if I've done anything dumb or could do anything better! This is my first ever try so I'm really feeling the learning curve.



Parts List:

Item	Cost	Part	Notes	Link
A	$707	Panels	12/24	(1) 200 WATT 24 VOLT SOLAR PANEL BACK ORDER — RICH SOLAR
B	$1,006	Batteries	12/24v	Deep Cycles 3.2v 280ah Lifepo4 272ah Lishen Lifepo4 Battery - Buy Lifepo4 Battery 280ah 3.2v,Lishen Lifepo4,Lifepo4 272ah Product on Alibaba.com
C	$227	Amp Solar Charge Controller	24v	Amazon.com: Victron Energy SmartSolar MPPT 100V 30 amp 12/24-Volt Solar Charge Controller (Bluetooth): Industrial & Scientific
D	$128	BMS	24v	8s BMS 100a LifePo4 Battery Management System for 24v DIY Batteries, Programmable, Bluetooth Included. – Overkill Solar
E	$260	Inverter	24v	AmazonSmile: Xijia 2500W (Peak Power 5000W) Pure Sine Wave Inverter DC 24V to AC 120V 60HZ Solar Converter for Home Use car (DC24V (Range 20V-30V) 2500W): Car Electronics
F	$36	12V Transformer	24v to 12v	AmazonSmile: uxcell New BIG-Size Voltage Converter Regulator DC/DC DC 24V to DC 12V 40A 480W Buck Transformer Waterproof: Electronics
G	$12	Entry Gland	2-6mm	AmazonSmile: Link Solar Weatherproof ABS Solar Double Cable Entry Gland for All Cable Types 2mm² to 6mm² for Solar Project on Rv, Campervan, Boat: Garden & Outdoor
H	$16	Inverter Fuse	250amp	AmazonSmile: WindyNation ANL Fuse Holder + ANL Fuse (2pcs 250A Fuse): Car Electronics
I	$27	Charge Controller Breaker	40amp	AmazonSmile: T Tocas 50 A Circuit Breaker amp breakers with Switch Manual Reset for Boat Marine RV Yacht Battery Trailer Bus Truck, 12V - 48V DC, Waterproof (50A): Automotive
J	$49	BusBar	250amp	AmazonSmile: Blue Sea Systems 250 Amp MaxiBus BusBar with 6 studs, 2126: Sports & Outdoors
K	$66	Fuse Box	2x	AmazonSmile : Blue Sea Systems 5025 ST Blade Fuse Block - 6 Circuits with Negative Bus and Cover, 3.32'' x 4.89'' : Auxiliary Fuse Block : Sports & Outdoors
L	$28	Breaker	30amp	AmazonSmile: T Tocas 30 Amp Surface-Mount Circuit Breakers with Manual Reset, 12V- 48V DC, Waterproof (30A): Automotive
M	$52	GFCI Panel Mount	20amp	Leviton Ground Fault Circuit Interrupters - LevitonProducts.com
N	$5	Junction Box	1x	Round Weatherproof Box, Five 1/2 or 3/4 in. Threaded Outlets, Gray: Electrical Outlet Boxes: AmazonSmile: Industrial & Scientific
P	$18	Outlet	4x	Journeyman-Pro 5279 15 Amp 120-125 Volt, NEMA 5-15 Flanged Outlet, Black Commercial Grade, 2 Pole-3 Wire, Straight Blade Plug Charger Receptacle (w/Front Cover) - - AmazonSmile
M	16	BusBar	100amp	AmazonSmile: Blue Sea Systems 100 Amp Mini BusBar with 4 studs and a cover, 2315: Sports & Outdoors
	$609	Fridge	12v/24v	TF65 Semi- Truck and commercial truck refrigerator (truckfridge.com)
	$25	Lights Ceiling	12v	AmazonSmile: acegoo RV Boat Recessed Ceiling Light 4 Pack Super Slim LED Panel Light DC 12V 3W Full Aluminum Downlights, Warm White (White): Automotive
	$60	2 Gear Fans	12v	AmazonSmile: Noctua NF-A20 PWM, Premium Quiet Fan, 4-Pin (200x30mm, Brown): Computers & Accessories
	$21	Fan Controller	12v	AmazonSmile: Noctua NA-FC1, 4-Pin PWM Fan Controller (Black): Computers & Accessories
	$72	4x 110V		Journeyman-Pro 5279 15 Amp 120-125 Volt, NEMA 5-15 Flanged Outlet, Black Commercial Grade, 2 Pole-3 Wire, Straight Blade Plug Charger Receptacle (w/Front Cover) - - AmazonSmile
		RV Ceiling Fan
		USB Ports
		USB-C Ports
		12V Ports
		Switchboard

Van on the way!

 

[FilterGuy]

Hey DIY Solar Power Forum, really excited to be working on the designs for my first ever solar build. I designed this build to power my office and living space in my 1990s Toyta Hiace. The van is still on its way from Japan and I've already ordered the batteries (Lishen) from Alibaba. Have a look at my diagram and please let me know if I've done anything dumb or could do anything better! This is my first ever try so I'm really feeling the learning curve.

View attachment 45365

Parts List:

Item	Cost	Part	Notes	Link
A	$707	Panels	12/24	(1) 200 WATT 24 VOLT SOLAR PANEL BACK ORDER — RICH SOLAR
B	$1,006	Batteries	12/24v	Deep Cycles 3.2v 280ah Lifepo4 272ah Lishen Lifepo4 Battery - Buy Lifepo4 Battery 280ah 3.2v,Lishen Lifepo4,Lifepo4 272ah Product on Alibaba.com
C	$227	Amp Solar Charge Controller	24v	Amazon.com: Victron Energy SmartSolar MPPT 100V 30 amp 12/24-Volt Solar Charge Controller (Bluetooth): Industrial & Scientific
D	$128	BMS	24v	8s BMS 100a LifePo4 Battery Management System for 24v DIY Batteries, Programmable, Bluetooth Included. – Overkill Solar
E	$260	Inverter	24v	AmazonSmile: Xijia 2500W (Peak Power 5000W) Pure Sine Wave Inverter DC 24V to AC 120V 60HZ Solar Converter for Home Use car (DC24V (Range 20V-30V) 2500W): Car Electronics
F	$36	12V Transformer	24v to 12v	AmazonSmile: uxcell New BIG-Size Voltage Converter Regulator DC/DC DC 24V to DC 12V 40A 480W Buck Transformer Waterproof: Electronics
G	$12	Entry Gland	2-6mm	AmazonSmile: Link Solar Weatherproof ABS Solar Double Cable Entry Gland for All Cable Types 2mm² to 6mm² for Solar Project on Rv, Campervan, Boat: Garden & Outdoor
H	$16	Inverter Fuse	250amp	AmazonSmile: WindyNation ANL Fuse Holder + ANL Fuse (2pcs 250A Fuse): Car Electronics
I	$27	Charge Controller Breaker	40amp	AmazonSmile: T Tocas 50 A Circuit Breaker amp breakers with Switch Manual Reset for Boat Marine RV Yacht Battery Trailer Bus Truck, 12V - 48V DC, Waterproof (50A): Automotive
J	$49	BusBar	250amp	AmazonSmile: Blue Sea Systems 250 Amp MaxiBus BusBar with 6 studs, 2126: Sports & Outdoors
K	$66	Fuse Box	2x	AmazonSmile : Blue Sea Systems 5025 ST Blade Fuse Block - 6 Circuits with Negative Bus and Cover, 3.32'' x 4.89'' : Auxiliary Fuse Block : Sports & Outdoors
L	$28	Breaker	30amp	AmazonSmile: T Tocas 30 Amp Surface-Mount Circuit Breakers with Manual Reset, 12V- 48V DC, Waterproof (30A): Automotive
M	$52	GFCI Panel Mount	20amp	Leviton Ground Fault Circuit Interrupters - LevitonProducts.com
N	$5	Junction Box	1x	Round Weatherproof Box, Five 1/2 or 3/4 in. Threaded Outlets, Gray: Electrical Outlet Boxes: AmazonSmile: Industrial & Scientific
P	$18	Outlet	4x	Journeyman-Pro 5279 15 Amp 120-125 Volt, NEMA 5-15 Flanged Outlet, Black Commercial Grade, 2 Pole-3 Wire, Straight Blade Plug Charger Receptacle (w/Front Cover) - - AmazonSmile
M	16	BusBar	100amp	AmazonSmile: Blue Sea Systems 100 Amp Mini BusBar with 4 studs and a cover, 2315: Sports & Outdoors
	$609	Fridge	12v/24v	TF65 Semi- Truck and commercial truck refrigerator (truckfridge.com)
	$25	Lights Ceiling	12v	AmazonSmile: acegoo RV Boat Recessed Ceiling Light 4 Pack Super Slim LED Panel Light DC 12V 3W Full Aluminum Downlights, Warm White (White): Automotive
	$60	2 Gear Fans	12v	AmazonSmile: Noctua NF-A20 PWM, Premium Quiet Fan, 4-Pin (200x30mm, Brown): Computers & Accessories
	$21	Fan Controller	12v	AmazonSmile: Noctua NA-FC1, 4-Pin PWM Fan Controller (Black): Computers & Accessories
	$72	4x 110V		Journeyman-Pro 5279 15 Amp 120-125 Volt, NEMA 5-15 Flanged Outlet, Black Commercial Grade, 2 Pole-3 Wire, Straight Blade Plug Charger Receptacle (w/Front Cover) - - AmazonSmile
		RV Ceiling Fan
		USB Ports
		USB-C Ports
		12V Ports
		Switchboard

View attachment 45360
Van on the way!

Overall, it looks like you have a pretty good start on the design.
For some reason I can't post more than a few hundred characthers so I will give feedback in multiple posts.

You have a regular 30A breaker in series with the 20A CFGI breaker. Why both?

 

[FilterGuy]

The 20A CFGI breaker will limit you to 2400W AC. The inverter is 2500WAC. However the fuse on the battery is big enough for 6000W,
I imagine you were trying to size it for surges. This is OK, but that is bigger than needed and it means you need to be useing 4/0 cable.... I would recommend using something more like a 150A or even a 120A fuse. This will allow your cabling to be much smaller

The 100A BMS is just big enough for 2400W. Therefor it is not big enough for the max on the AC plus DC loads. If you are confident you will never use more than 2400W this will work, but it is tight. I like to have more headroom in the BMS capability.

 

[FilterGuy]

Are the numbers next to the wires the AWG size of the wires? If so, some of the wires are too big and some are too small.

I would put smaller fuses on the wires going to the fuse box. (They should be right after the main fuse).

You may want to review this:

DC Fuse and breaker Sizing and Placement

To get the paper, click on the orange button at the top of the page The attached presentation gives the fundamentals for picking fuse/breaker sizes and describes where in the circuit they should be placed. You can download the presentation by...

diysolarforum.com

 

[elpulpo]

Overall, it looks like you have a pretty good start on the design.
For some reason I can't post more than a few hundred characthers so I will give feedback in multiple posts.

You have a regular 30A breaker in series with the 20A CFGI breaker. Why both?

Thanks so much! My thinking with the Breaker/CFGI is that the breaker protects the system and the CFGI protects the humans. Because of the way CFGI detects a difference in the current on the positive and negative lines I thought it would be an extra safety should someone short themselves to the AC without blowing the 30amp breaker. I could be totally wrong on this but that was my intention.

 

[FilterGuy]

Thanks so much! My thinking with the Breaker/CFGI is that the breaker protects the system and the CFGI protects the humans. Because of the way CFGI detects a difference in the current on the positive and negative lines I thought it would be an extra safety should someone short themselves to the AC without blowing the 30amp breaker. I could be totally wrong on this but that was my intention.

The CFGI is *also* a regular 20A breaker. Unless the short is between the two, the CFGI will always blow first.

 

[elpulpo]

The 20A CFGI breaker will limit you to 2400W AC. The inverter is 2500WAC. However the fuse on the battery is big enough for 6000W,
I imagine you were trying to size it for surges. This is OK, but that is bigger than needed and it means you need to be useing 4/0 cable.... I would recommend using something more like a 150A or even a 120A fuse. This will allow your cabling to be much smaller

The 100A BMS is just big enough for 2400W. Therefor it is not big enough for the max on the AC plus DC loads. If you are confident you will never use more than 2400W this will work, but it is tight. I like to have more headroom in the BMS capability.

I see. Actually, I just picked that battery fuse off of one of the prebuilt systems lists. I'll probably size it down.

I'll think about my loads more carefully and then size the BMS/Inverter more appropriately. Almost all my devices are DC with the only regular AC loads being laptops and battery chargers. I picked an upsized Inverter in the off chance I wanted to run corded power saws or other similar tools.

 

[MisterSandals]

You should put a switch or breaker between solar array and SCC to be able to turn off charging.

Is there a reason you chose 3 of those smaller expensive panels? I cannot tell if it is a size or arrangement issue. But $700 for 600w is a lot these days. Check craigslist for panels in your area.

 

[elpulpo]

You should put a switch or breaker between solar array and SCC to be able to turn off charging.

Is there a reason you chose 3 of those smaller expensive panels? I cannot tell if it is a size or arrangement issue. But $700 for 600w is a lot these days. Check craigslist for panels in your area.

Ah good call. I'll add in a switch. Yeah I tried a lot of different panel arrangments and checked craigslist. Those 200w panels just happen to fit really well on my van. Kinda gnashed my teeth on it but couldn't find another way to fit everything I want on the roof.

 

[HRTKD]

If you're using a rack system, the panels can be butted up against each other very close (but some space will still be required). If you're using the standard Z brackets, you'll need a lot more space between the panels.

You're using a negative common bus bar, why not a positive common bus bar? You can stack only so many cable lugs on one bolt before you run out of threads. The bus bar makes it a lot easier should you need to disconnect one cable.

 

[elpulpo]

If you're using a rack system, the panels can be butted up against each other very close (but some space will still be required). If you're using the standard Z brackets, you'll need a lot more space between the panels.

You're using a negative common bus bar, why not a positive common bus bar? You can stack only so many cable lugs on one bolt before you run out of threads. The bus bar makes it a lot easier should you need to disconnect one cable.

I was wondering about that from a safety perspective if it's ok to run the positive terminals on a bus bar. Kinda new to all this so being cautious.

 

[richard cabesa]

Definitely put in a bus bar for the positive. Stacking many on one terminal is just bad practice. And you never know when you will add more things than you imagined. You will be ready for additions