Circuit breaker or fuse?

I would want a way to disconnect power to the inverter quickly in an emergency. A breaker allows for that. I'm not sure why you think you wouldn't need a spare fuse. I would think a spare would be a good idea. Sometimes inverter go a little crazy and power cycling them will reboot the processor and make it work again. It's a lot easier to power cycle with a breaker as well.

dodge guy wrote:
So. I’ll be installing a 3000W inverter and with that, what is better? A 300A circuit breaker or an ANL fuse? I like the fuse so I don’t have to keep spare fuses, but a circuit breaker will be easier to just reset.

look at or estimate what the MAX short circuit current of your battery bank could be. Make sure whatever fuse or breaker you choose will interupt that current level.

When I did checking for my install of a 1000W inverter, ANL fuses worked, most reasonably sized, affordable, obtainable circuit breakers weren't spec'd for the battery bank short circuit current capability.

Fuse. Quality DC breakers in the 300+ amp range seem to be expensive. Never opened the fuse on mine.

time2roll wrote:
Fuse. Quality DC breakers in the 300+ amp range seem to be expensive.

Yep, there are a lot of cheap Chinese breakers out there on the market that I wouldn't trust.

A decent-quality one isn't cheap.

Size the fuse or breaker to protect the wire connecting the battery to the inverter. For example, I am using #4 wire to connect my 600W inverter, so a 60a breaker is installed. The larger the wire, the bigger the fuser/breaker capacity you can have.

Ok. I’m OK with fuses, I’ll just have to carry a couple of spares just in case.
I will have A high amp shut off switch. And will be using 4/0 welding cable for power.
I will get the fuse instead.

KD4UPL wrote:
I would want a way to disconnect power to the inverter quickly in an emergency. A breaker allows for that. I'm not sure why you think you wouldn't need a spare fuse. I would think a spare would be a good idea. Sometimes inverter go a little crazy and power cycling them will reboot the processor and make it work again. It's a lot easier to power cycle with a breaker as well.

I just seen that. I missed typed. I like the circuit breaker because I don’t need fuses. But the fuses seem to be cheaper. And for as often as it sounds like they fail ( almost never) I would only need to keep a couple of extras.

dodge guy wrote:

KD4UPL wrote:
I would want a way to disconnect power to the inverter quickly in an emergency. A breaker allows for that. I'm not sure why you think you wouldn't need a spare fuse. I would think a spare would be a good idea. Sometimes inverter go a little crazy and power cycling them will reboot the processor and make it work again. It's a lot easier to power cycle with a breaker as well.

I just seen that. I missed typed. I like the circuit breaker because I don’t need fuses. But the fuses seem to be cheaper. And for as often as it sounds like they fail ( almost never) I would only need to keep a couple of extras.

Now that is good logic!

Houses used to use fuses, but now circuit breakers, obviously, you can just reset them when they trip instead of buying a new fuse each time. Breakers also work as an on/off switch.

I have one of these in a 100amp and it works just fine, $15 or so, though I havent tested it or made it trip.
ebay link to 300 amp breaker ebay 300 amp breaker
I actually have 4 total of different amp ratings for my solar and battery and vehicle connections.

There are also breakers that will reset themselves after they trip after they cool down, so are kind-of an automatic resetting breaker, kind-of.
Of course you will probably never trip a fuse anyway, so not a big deal to have two spare fuses on hand either.

* I dont get why you would want to buy an expensive shut-off switch, then put in a fuse when a breaker is bother a switch and a "fuse" in application.

breakers are the better choice, but like nentions cost a bit more. I use them on my wires two and from my solar panels and on the charge side as I can use them as a disconect also.

Steve