Everything on the Solar setup was existing. The fuse holder was a Blue Seas brand waterproof inline fuse holder. The same fuse holder was used for the house/inverter battery bank and the starting battery. The starting battery fuse shows no corrosion. As I mentioned in an earlier thread I replaced the batteries several weeks prior to the fuse melting. When I put the cover on the battery box the fuse that failed got pushed down with the cover directly over the vent on the battery. The fuse holder is sealed with a gasket but I am wondering if the battery gases could of got in and caused corrosion. When I discovered the smoke and took the cover off the battery box the upper part of the fuse housing where the fuse would have been was burned up and pretty much gone, and there was still a glow between the two sides of the open fuse housing at which time I shut everything down.
I feel whatever happened to the fuse had to be involved with the heavy amp draw on the inverter at the time. If I remember correctly at the time it occurred the inverter panel was reading around 125 amps with the microwave running. I also remember looking at the solar panel somewhere around the time this occurred and it was about 13amps but it was overcast so that was fluctuating as clouds moved over. At the time it happened my wife had used the microwave, then the toaster and then the microwave again so the inverter was getting hit hard for several minutes. The company that makes the solar controller said the inverter can not pull anymore power through than what the solar panel is providing. My question is with the heavy draw on the battery bank, which one side of the fuse is connected to, and the normal say 12-13 watts on the other side coming in from the panel, how can that scenario cause the excess heat that caused the fuse to fail? I do not think the fuse would of burned up like it did with a solar charge coming in and a regular draw on the batteries as it has been operating like that without issue for me. If the draw on the batteries can not pull more amps than what the solar panels are providing does it do anything else like try to pull the power through faster or something that could overheat a connection point? Just trying to get a better understanding.
Since the fuse melted I have had the solar system disconnected but am now in the process of hooking it up again. I ran 8 gauge wire from the solar controller for both battery banks with separate 30amp Midi fuse holders mounted external from the battery box on the bulkhead. I will then be running 8 gauge wire from the fuse holder to a bus bar, mounted externally from the battery box as well, which will have all battery connections other than any sensor wires and wires connecting the battery banks which will be directly to the batteries.
Once it is hooked back up I will run some test putting a heavy load on the inverter and checking amp draw through the wiring. I will post back once I get it going.