Okay, I understand the fuses, the disconnects and breakers please?
In this context, the fuses should be sized to protect the cables, thats all.
I have 48V, capable of pushing something like 60,000 amps into a short circuit. I definately don't want that!
I have 35 sq mm cable to the inverter (2AWG?) - but only a short run, 1 metre (3 feet).
Since my inverter is a maximum output of 10,000 watts, I could pull 200A peaks, so the fuses have to be at least that big.
200 amps should protect my cables in the event of a catastrophic failure somewhere.
Breakers are (*almost always*) a bad thing with wind turbines. You don't want them opening during a high wind event and leaving your mill unloaded to fly apart, so the breakers in my system are only between the battery bank and the inverter itself, and are sized slightly over the maximum current the inverter should normally take in operation.
Finally, the isolators. These are are rarely used. They are not normally used to turn anything on or off (as in, to interrupt a working circuit) - they are not rated for that purpose. They're just to isolate a battery from the rest of the system (while they're not actually being charged or discharged) so you can safely work on a battery string, or if you wanted to charge a cell by itself, or let them sit to check their charge etc.
You are ahead of me, I am presently putting in solar, plan on adding wind, excellent site; but DC isolation is a bit difficult wth off the shel parts and suitable AIR values.
In the *solar* part of my setup, I have 6 arrays which I bring in seperately, so I can isolate and meter each to see how they're going.
Here's the breaker panel before the cover went on. The breakers are double-pole (break both + and -) and are (from memory) rated for 500V DC, 10A, and *ARE* rated for interrupting that current at that voltage *DC*. The breakers were more than cheap AC breakers, but not stupid money. I think I paid about $25 each for them, but they're nice insurance.
