300A DC circuit breaker

[Luthj]

When running up against the limits of available fusing/breakers for AIC, you can more accurately calculate the fault current by including the bus bar/wiring resistance between the pack and the fuse/negative bus bar.

When working with multiple parallel batteries in this size of pack, its best to fuse each pack individually as a branch. At the busbar you may need another fuse depending on the wire sizing and your load. In some cases its not necessary to have a main fuse if a single pack dropping out won't cause a cascade blow/trip of the fuses.

 

[Off Grid Thad]

As far as I understand, there is no distance dimension to safe ampacity

Distance relates to the voltage drop side of wire sizing, not the ampacity side. Someone correct me if I am overlooking something.

There is no (practical) wire size rated for 1800A, however, if you fuse for the wire, and fuse each battery circuit + the main circuit, you would not need wire sized for 1800A, right?

That was a bit of sarcasm from me. Most people think I am irritating that way.

 

[Dzl]

That was a bit of sarcasm from me. Most people think I am irritating that way.

I have a very poorly calibrated sarcasm meter on the internet.

Looking at an NEC chart, it looks like you could triple up 1000 KCMIL for a little over 1800A current carrying capacity:
This x3: ?