Is my 800w 12v system ready to be plugged in? Any input is greatly appreciated


New Member
Feb 8, 2022
Please let me know if i’ve got to fix anything in my build, all the thicker wires are 4/0AWG and the thinner ones are 4AWG.
List of things in this build:
-80 Amp MPPT Solar Charge Controller
-125VDC MidNight Panel Mount Breaker
-300Amp Class T Fuse
-12V 3000W Continuous 6000W Surge Peak Power Pure Sine Wave Inverter
-3 12V 206ah lithium batteries (wiring them to keep them at 12v)
-4 200W Solar Panels
-400amp solid copper Busbars (positive and negative)


  • 4699C3B2-2EF6-4CA7-923E-8FC298854401.jpeg
    1.3 MB · Views: 22
  • 511EBF12-F5C3-4EC5-ABD8-242BD29321E1.jpeg
    1.2 MB · Views: 22


Full-time Solar-powered Trailer Life
Nov 16, 2019
Posting a schematic of your setup might help. It's really hard to see much in the pictures.

The key will be properly wiring your 3 batteries in parallel so they stay balanced. If you haven't already, see chapter 3 of the "Wiring Unlimited" document from Victron:

Your Class T main battery fuse might be a bit small. A 3000W inverter on a 12V system can pull up to 300A. The 4/0AWG wiring is good for that. But the fuse should be 300A x 125% which rounded up gives you 400A. The 300A fuse will work but you risk a nuisance trip when maxing out the inverter. However, if you decide to go with a 400A fuse then 400A bus bars are too small. You would want 500A bus bars to ensure the fuse is the weak link.

The 80A SCC is larger than you need with only 800W but it does give you room to add another panel or two in the future.

What is your panel arrangement? Make sure the Voc of the panel array is under the 125V or your PV breaker will be an issue.

Do make sure your SCC is connected to the battery BEFORE you connect the PV to the SCC.