Proposed 24V wiring diagram

[TomM]

Attached is my proposed wiring diagram for the 24V system. Please look it over. My plan right now is to manually isolate the system when on shore power. I wish now I had used and inverter/charger with an auto transfer switch.

Component list:
1. 3 Rich Solar 200W, 24V solar panels hooked in parallel to provide ~37V, ~16 amps charging current (not ordered).
2. EPEver MMPT MT50, 1200W, 24V designed for 150V and 40A (not ordered).
3. Home built 280Ah, 24V LiFePO4 battery. 8 cells ordered and in transit.
4. Overkill Solar BMS for 8 cell, 24V LiFePO4. Received.
5. Giandel 3000W, 24V, pure sine inverter to run lights and the microwave. Received.
6. UXCel 24-12V converter, 40A. Received.

 

[pollenface]

All looks good to me

 

[wmills_92105]

Your wire size changes going to the dc2dc unit. Does that need a fuse?

 

[Pnw_steve]

External auto transfer switches can be had for around $70. You could certainly add one to your system without too much trouble.

I am getting ready to install this one: https://www.amazon.com/Go-Power-TS-...ords=Rv+Transfer+Switch&qid=1608177021&sr=8-4

 

[TomM]

I don't know if my dc2dc unit needs a fuse. I am confused by Will's circuit where he uses a fuse one place and a circuit breaker another. Why use a fuse vs CB? Where do I need protection?

Tom

 

[wmills_92105]

I am using a CB so it can also be used as a main on/off switch. They are more speedy though.

 

[Factory400]

I would highly recommend:
Swap 2AWG for the 4AWG
All the 10AWG is undersized as well - especially the "Up to 85A at 4ft"


This is a low voltage DC system - your concern is voltage drop, not the absolute max ampacity you find on a chart that is based on temp rise.
Skimping on the copper is simply not worth the drop or jacket softening heat you get when you push a wire to hard.

 

[TomM]

Thanks for the feedback. Tom

 

[Max Q]

I have nearly the exact same setup, except 2 - 24v A123 batteries (from that one vid Will did) and 2 - 40A EPever SCC's. Was looking for an approved schematic.

My batteries should assimilate to this setup if I hook them up in parallel.

Not sure about the SCC's tho. Should I add 2 - buss bars before the SCC's in order to "split" the cables coming from solar to go into each SCC individually?

 

[APhoton]

Attached is my proposed wiring diagram for the 24V system. Please look it over. My plan right now is to manually isolate the system when on shore power. I wish now I had used and inverter/charger with an auto transfer switch.

Component list:
1. 3 Rich Solar 200W, 24V solar panels hooked in parallel to provide ~37V, ~16 amps charging current (not ordered).
2. EPEver MMPT MT50, 1200W, 24V designed for 150V andI 40A (not ordered).
3. Home built 280Ah, 24V LiFePO4 battery. 8 cells ordered and in transit.
4. Overkill Solar BMS for 8 cell, 24V LiFePO4. Received.
5. Giandel 3000W, 24V, pure sine inverter to run lights and the microwave. Received.
6. UXCel 24-12V converter, 40A. Received.

I'm a novice but 4AWG wire from battery to inverter and back seems too small. For 24v/3000w inverter, I would think a minimum of 1/0 or 2/0 would be necessary. Check with some of the more knowledgeable people on this forum