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29 Replies
- GordonThreeExplorerThese big fuses have a name ... the catastrophic failure fuse
- MrWizardModeratorNo I don't think it's going to handle 8000 amps short
Why should it
You want it to trip at 300 - pianotunaNomad IIIFuse with class T to the rating of the wire.
- DrewEExplorer II
starcraft69 wrote:
This is what i was thinking Is 300amp breaker the right size?
What size wire will you be using? That's the main purpose of the fuse--to prevent a fire from the wire overheating in the event of a short circuit.
300A is a reasonable ballpark value, though larger might be better as most inverters have a surge capability somewhat beyond their nominal rated capacity. (Well, decent inverters do; all bets are off for questionable unknown brand inverters from overseas.)
Edit: The inverter instructions may have some recommendations on power lead wire size and fusing. - GordonThreeExplorerWhat's the DC current interrupt rating of this 300 amp breaker? Can it handle the direct short capacity of your battery bank? Example: my bank is rated at 8000 amps direct short
- starcraft69Explorer
KD4UPL wrote:
I wouldn't use the ANL, the Class T is the fuse you want. But, I would prefer a breaker. It will act as a disconnect switch if you need to shut off power to the inverter for some reason. And, if it every trips, you can reset it instead of having to find/order and install a new fuse.
Blue Sea, Outback, and Midnite solar (as well as others I'm sure) will have the breaker you need.
This is what i was thinking Is 300amp breaker the right size? - KD4UPLExplorer III wouldn't use the ANL, the Class T is the fuse you want. But, I would prefer a breaker. It will act as a disconnect switch if you need to shut off power to the inverter for some reason. And, if it every trips, you can reset it instead of having to find/order and install a new fuse.
Blue Sea, Outback, and Midnite solar (as well as others I'm sure) will have the breaker you need. - GordonThreeExplorerNeither ... at that amperage, go with a Class T fuse
for background, read about interrupt rating and direct short rating on batteries. - 2oldmanExplorer IIFuse. I guess I could look it up, but I didn't know DC used breakers.
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