diy solar

diy solar

Pure 12V 400watts set up (no inverter)

Dambuhala

New Member
Joined
Jul 3, 2022
Messages
5
I’m new and totally no electrical experience, I’m following Will’s 400 watts set up but with modification and that is no inverter because I want pure 12V only for simplicity and cost. What will be my drawing if the inverter will be removed in the picture? Do I need bus bar for negative wirings? Do I need main fuse immediately before my positive battery terminal? My loads are roof fan, food cooler, led light, cell phone, laptop and other gadgets. I have two battleborn 12V 100AH, TracerBN4215 MPPT 40amp, one 455watts solar panel (JA solar), fuse box for DC appliances, 50amp circuit breaker for my charge controller. So far, what I have done is installed my solar panel at the roof of my van and parallel connected the two batteries. I really appreciate your inputs, parts to be installed if I missed anything, and drawings if possible.

4DC65581-B0B2-4FD3-92D9-46B5B49109E4.jpeg

461EE40E-8093-4211-8121-40B379CB52AC.jpeg
 
In the first picture you remove the inverter and its two wires and that's it. Everything else stays. The size of the main battery fuse may change. It basically depends on the total load of your 12V DC loads.

Make sure that when you connect the two batteries to the rest of the system that the main positive wire goes from one battery and the main negative wire goes from the other battery.

I'm curious why you ended up getting BB batteries if the goal is to save money. You bought the most expensive batteries possible. They are very good batteries from a good company but there are certainly cheaper quality options.
 
Hi rmaddy thank you for the quick reply. The amount saved for inverter goes to battery. I think buying BB battery will be cost effective in the long run considering its life span compared with cheap Chinese battery in our local market. I’m okay with SOK battery but the seller does not deliver in my address so I ended up with BB which cost almost my arms and legs. I’m living part-time for more than 6 years, I save a lot and now just bought my stuffs. May be a full time living is waiting for me once I have done this correctly. I’m tired of charging all my things at work and using it in my van.
 
Connect your main fuse as near the battery pack positive as practical and run a cable from this to a buss bar.
Connect to this buss bar fuses or breakers to feed to the solar controller and fuse box. Fuses are preferred for cost and reliability, unless you use Bluesea/Bussman breakers. Having separate fused paths helps fault finding and creates a more secure system.
My guess is your 12v appliances are not going to use more than 50 amps total.
My other guess is that some time in the future you will install a low power inverter, so plan at this stage how it will be connected.
diy solar july 22.jpg
note 1
the preferred main protection fuse for lithium batteries is a class t fuse, less acceptable is a MRBF for a 12v system, even less current withstand is ANL fuse, (better than no fuse at all).

note 2
if using breakers rather than fuses, a positive buss bar is needed. With fuses its possible to use a fuse distribution unit that combines the buss bar and fuse holders, Victron, Bluesea, and others van supply such distribution fuse holders.

Mike
 
What is the amp rating on the solar charge controller?
 
If the scc is 30 amps or less then we can dispense with the busbars and just build the system around a decent fuse block.
Also if the scc output is less than 24 amps then we can use 10 awg wire and a 30 amp fuse to one of the branch circuits on the fuse block.
 
Last edited:
I believe Tim's remark relates to the fact that the OP states which SCC they will be using.

Yes it was and SmoothJoey is usually on the ball in picking up things. My apologies Joey but I couldn’t resist :). Hope you have had your coffee this morning.☕

Whilst I’m here rmaddy I have to say, I read many of the threads just out on interest and think it is absolutely fantastic how people like yourself, Joey, Mike and many others go out of your way to help so many people.

Take care all.
 
Connect your main fuse as near the battery pack positive as practical and run a cable from this to a buss bar.
Connect to this buss bar fuses or breakers to feed to the solar controller and fuse box. Fuses are preferred for cost and reliability, unless you use Bluesea/Bussman breakers. Having separate fused paths helps fault finding and creates a more secure system.
My guess is your 12v appliances are not going to use more than 50 amps total.
My other guess is that some time in the future you will install a low power inverter, so plan at this stage how it will be connected.
View attachment 101260
note 1
the preferred main protection fuse for lithium batteries is a class t fuse, less acceptable is a MRBF for a 12v system, even less current withstand is ANL fuse, (better than no fuse at all).

note 2
if using breakers rather than fuses, a positive buss bar is needed. With fuses its possible to use a fuse distribution unit that combines the buss bar and fuse holders, Victron, Bluesea, and others van supply such distribution fuse holders.

Mike

Great info. Really appreciate it.

Actually, I have a two-burner LPG gas stove which uses 220V electronic ignition, however since my goal is purely 12V only, I decided to use a lighter. I simply turn on the knob and use the lighter.
 
Last edited:
Back
Top