So many questions

[Wally Arave]

I have a 9 panel system, off grid, 8 6 V batteries (48V system) that about 1.5 years ago one of the batteries melted down. The business that installed them is now out of business. I've been working on resurrecting it. Near as I can tell, there was a loose connector and that's why the battery melted down. I have replaced two batteries, checked all the wiring, ordered some new cabling for between the batteries. The invertor is a Pure Sine Wave Combined Invertor and Charger by Sigineer Power. The Controller is an MPPT Series ML4860. I have put a lot of study and thought into the system in general. My concern in all the diagrams I see there are recommendations for fues on the load lines such as between batteries and controller and invertor to the breaker box, etc. I would like some recommendations on the types of fuses to put in the lines, and secondly, where do you find solar equipment? When I talk to people at Home Depot or Lowes, I get the head scratcher answers..I've reached out to local solar providers and they don't want to touch it if they didn't install it. It worked fine for a year, I honestly think the installers left a line loose and it fried. Also, I'm a little perplexed that the controller box attached to the invertor on the appropriate + and - posts, and the batteries attached to the same posts on the invertors. Should these two systems...battery system and the invertor piece be wired through a junction box separately? Thanks for any advice..the batteries are Duracell Golf Cart 6V batteries. I'm actually kind of excited about solar..now that I'm learning it and working it, I wish I had been more focused when the system was installed and asking questions.

[chrisski]

Don’t go to Home Depot Lowes etc. I order from Amazon. I live in the fifth most populated area in the county, and there is not a walk in store to buy solar equipment. Of course many stores have it, but at much more than you’d pay through Amazon.

I like Victron Charge Controllers. Done over, I’d consider SANTAN solar because of the low panel prices and they are local to me.

For high Amperage fuses, I used an ANL fuse that is rated by the ABYC as primary battery rated. I mention that because there’s ANL audio fuses that do not have that rating. It sits in a Blue Sea ANL fuse holder. Afterwards, I saw a Class T may have been a better fuse because it blows quicker.

For lower amperge, I use MC4 Inline fuses, which in my case was 15 amps, and a variety of Midnite Solar 150 volt and 250 volt circuit breakers for between 10 amps and 30 amps.

I have a busbar that I used to wire my inverter, battery and charge controllers. After installing connectors on 7 studs on both the positive busbar and negative bus bar, I did find out that I could have put more than one lug on each stud. I don’t think you’ll need a junction box, but I wish I had a cover for my bus bar.

[Mike90250]

Your battery terminal melting is suggestive of a bad crimp on the terminal lug. They can "look" ok, but be bad inside

I prefer to use circuit breakers ( DC rated of course ) as the better ones are rated to be used as a switch too. Fuses are fine, but the fuse holder is seldom rated to disconnect if you need to shut down, or reboot a controller after a firmware upgrade. Breakers cost a bit more, but the requirement for spares on hand, is nil.