inverter fuse/breaker

Fuse. I guess I could look it up, but I didn't know DC used breakers.

Neither ... at that amperage, go with a Class T fuse

for background, read about interrupt rating and direct short rating on batteries.

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.

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?

What'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

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.

Fuse with class T to the rating of the wire.

No I don't think it's going to handle 8000 amps short
Why should it
You want it to trip at 300

These big fuses have a name ... the catastrophic failure fuse

MrWizard wrote:
No I don't think it's going to handle 8000 amps short
Why should it
You want it to trip at 300

I want it to be able to break an 8000 amp arc if something fails inside the inverter and Bat+ crowbars to ground.

The filling and design of a Class T insures this. An ANL doesnt... I don't know about circuit breakers, that's why I'm asking?