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I like your setup, but would like to try to convince you to swap that breaker for a blue sea / Buss 187 series.
 

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Advice appreciated! Just wondering... are breakers made in Mexico that much better than those made in China? About $90 for a 100A breaker ???

Before answering, remember our vans are made in Mexico, and their electrical is a bit short of spectacular... ;)
They are really a completely different grade / spec of breaker.

It is a marine breaker that is engine room qualified with a fairly high amp interrupt rating. This means that it is really rated and tested to deal with a dead short to ground from high output battery packs, even if it is damp and there are gasoline fumes in the air.

It is unfortunate that the price has nearly doubled since I designed them into my own product offerings a few year ago. I use both the panel mount and surface mount depending on the application.

It is important to clean the threads and contact surface prior to use.

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The one that you have currently tends to overheat and fail unfortunately. If you are only using it for fairly light loads it might not matter.

@GaryBIS has some experience with trying to use entry level CBs with mixed success IIRC.

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For me, it is a big deal if a breaker fails on a customer project because:
  • It puts doubt in the customer's mind about the rest of the build quality
  • It takes time to deal with the customer need on the phone / email, send them a replacement part, and then walk them through how to install it.
  • Time has real value to me, so even if I spent just 1 hr on a warranty issue that could have been avoided by using a higher quality / more expensive part - it is worth it.

For other people, this value of time might not be as important.

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The other factor is that it is challenging to obtain a 100 amp continuous capable wire connection inside of those breakers.
 
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Good info, and I understand that delivering a product for customers needs some more stringent parameters.

My current thinking is that...

- when the juiceBOX is being battery 4, the most draw should be about 50A if the 4 batteries distribute the maximum fused 200A load evenly

- if I connect a 1000W inverter, load should be about 80A... might be the highest load I'd use.

- the cost of the name brand breaker is more than I spent on the whole JiuceBOX!

- I thought about an ANL fuse... have the parts already and it would fit well, but... I like the idea of using the breaker as an on/off switch too...

So, I may think about it a bit and decide about the Blue Sea/ Buss breaker... not sure that an 80A breaker (with it's built in time lag) wouldn't be OK for my application.

Hmmmmm.......
I completely agree with using a breaker in that location and for the reasons that you noted. I use them for the exact same reasons.

Given that you already have the set up built, it is probably worth just using it for a while in it's intended use and see what happens.

Maybe there is a way to leave space for the other breaker type for if / when the existing one gives up.

Usually they fail "tripped" so it is more of an inconvenience than a real danger.

Just like a fuse, a thermal breaker is essentially a resistor so they will get warm during use - so slightly over sizing it rating wise isn't a big deal and probably a good thing.

Officially the rating is supposed to be lower than wire ampacity, but as a practical matter, what you are protecting against is a dead short. The internal battery BMS might trip before the breaker even if you run a lower amp rated breaker.

That is actually the other reason to use a breaker in that application. In most modern LiFe batteries, the internal BMS will trip from an overload, etc but not damage it. To reset the BMS, you have to isolate the battery (+) from external voltages / bus bar and a breaker is a very convenient way to do this without getting the tools out to swap a fuse in and out.

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This is one of the reasons that I suggest 24 volt systems. One breaker shuts down and isolates 2 batteries instead of just 1.
 
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