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2000w inverter with long wire, will it work (safely)?

Scary thread...

I also use one of those T Tocas breakers on my SCC to battery connection, an upgrade from the really cheapo ones from amazon.
Lots of pro's here recommending if you're gonna run one of those, at least get a Eaton Bussman one though. Even the former are kind of cheapo - not enough contact inside and they do get hot, and they cause resistance to your current, and not recommended. It's one thing for a 40A, quite another for a 250A.

If it were me I would install an ANL fuse - that's what I have done, and no heating through them. Again, a Bussman fuse, not the cheapo stereo blades that are so popular.
 
Scary thread...

I also use one of those T Tocas breakers on my SCC to battery connection, an upgrade from the really cheapo ones from amazon.
Lots of pro's here recommending if you're gonna run one of those, at least get a Eaton Bussman one though. Even the former are kind of cheapo - not enough contact inside and they do get hot, and they cause resistance to your current, and not recommended. It's one thing for a 40A, quite another for a 250A.

If it were me I would install an ANL fuse - that's what I have done, and no heating through them. Again, a Bussman fuse, not the cheapo stereo blades that are so popular.
I do want to use a fuse because the manual reset breaker also serves as the true kill switch for storage. I do have a beefy 300A switch but that one doesn't disconnect propane/co detector and trailer brake, for safety reason. when I put the trailer in storage/winterization, I charge the battery to about 60% and disconnect the breaker
 
Then get a real DC circuit breaker, or master cut-off switch. Putting that 250A cheapo breaker is like putting a dam in your river.
 
Then get a real DC circuit breaker, or master cut-off switch. Putting that 250A cheapo breaker is like putting a dam in your river.
Are you recommending a different brand? Or different type of breaker? I could not find a ‘real dc breaker’
 
Or a mini-breaker in an appropriate breaker box. Just make sure they're DC rated, not AC. And watch for polarity if you're using two-pole.
These are also common as a PV cutoff switch.

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You might also check into a BlueSea master cutoff switch, depending on your system voltage. I think these are rated for 48V.

Mini:

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Maxi:

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I also have one of those cheapo breakers. I have the T Tocas 60A breaker for solar out to battery(Victron 100/50) and a Gloso 150A breaker for battery shut-off(2-SOK 206Ah 12V in parallel) I’ve not measured any resistance on them and they have not gotten hot while using 1500Watt GoPower Inverter for extended periods. I rarely draw more than 130A for more then 5-10 minutes and most loads are under 30A. I figure the switch will malfunction due to being used as a shut off switch before it malfunctions as a breaker. I wouldn’t feel comfortable using these switches with much higher Amperage going thru them for safety concerns, just as others have stated but for what I have I totally trust them as they have been solid and dependable. They are good enough for my local marina and they have great reviews on Amazon so we can’t all be wrong can we?
I would be more concerned about creating more resistance by having to have the additional connections by adding a true shut off switch along with a fuse. That would add additional terminal lugs and more points of failure and areas that could get hot if a connection were to get loose or was bad. It’s also something to consider is it not?
 

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Yes, lots of clueless people can be wrong - we already know they're like sheep. LOL

Lots of complaints of voltage drop with them, heating on high load, and complete failure. YMMV
Knowledge is power. (y)

Nice setup - I would not use that breaker on the mains for a cut off. AFAIK your SOK has an internal fuse, so you're probly good there - a class-T is recommended for lifepo due to so much energy - they can arc across light duty fuses. IMO a master cutoff switch would work better there, assuming your battery is already fused.

You can check for voltage drop across it, and hit it with a laser-thermometer at the terminals, at full load.
I'm fine with them on the SCC - but same thing, watch for voltage drop. I also use one for my primary charge controller.

This one has since been replaced with a T Tocas one per Will's recommendation, but still others have suggested to only use the Bussman ones.
My main feed has a BlueSea master switch to isolate the lifepo pack.

 
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My 2000W inverter has a manual that recommends 2/0 awg for up to 20 feet round trip. Blue Sea chart lists 3% voltage drop at 200 amperes.
 
They are good enough for my local marina and they have great reviews on Amazon so we can’t all be wrong can we?
I doubt that many (if any) people who reviewed them on Amazon actually tested their fault trigger conditions. In a well designed system your breakers / fuses should never blow, so saying it "works great" is pointless unless the user witnessed it trip due to overload conditions.
 
I doubt that many (if any) people who reviewed them on Amazon actually tested their fault trigger conditions. In a well designed system your breakers / fuses should never blow, so saying it "works great" is pointless unless the user witnessed it trip due to overload conditions.
Well, a well designed system shouldn’t overload so I guess some of us will never know apparently. I’m not in the habit of pushing things to their limits just to test them out to see if they work. My 35000HD trucks Speedo says it does 140mph but I don’t think I’ve ever had it over 85. With my battery, BMS and cheapo breaker, It still “works great“ for my purposes, your expectations may be different and that’s fine. There are so many other areas of concern honestly like equipment not being UL listed or certified, cable sizes, manufacturers quality and build, inverter capacities, bus bar quality, lug crimp, etc., I’m sure we can find fault in every system. I’ve seen a few in Wills that I’ve questioned myself. I‘ve learned a lot in this build and I can assure you that in my next build, I will probably use higher rated and certified equipment based on recommendation that you and others have suggested. I can totally see and appreciate their benefits. Thank you! I will take your recommendations into consideration with this build and I will do more research into my systems points of failure. I think that’s the smart thing for anyone to do as I’m sure we’ve all made some sort of modification over time.
 
still “works great“ for my purposes, your expectations may be different and that’s fine
The issues with arc and fire sorta make the cheapos undesirable in my opinion. Throw an ohmeter on it maybe? I’d personally rather be unfused than use a breaker that could be smokey and sparky. Ymmv but mine doesn’t.

Just food for thought.
 
Forum members are just looking out for danger, trouble. An electrical fire can ruin your entire day. ;)
I love that pic with the red-hot glowing bus post, no tripped breakers or fuses. And the burned out sprinter van. :rolleyes: And the shorted board topper in the Phillipines. And the bus conversion chassis battery box. If this stuff goes south it's a $hit-show.

A lifepo system isn't a pickup truck. If you don't test it to YOUR limits then you don't even know if it will work right for you or not. It's silly not to test.

This thread is just plain scary. Wire sizing, fuses, and amps. What a party!! ? :ROFLMAO:
 
Forum members are just looking out for danger, trouble.

This thread is just plain scary. Wire sizing, fuses, and amps. What a party!! ? :ROFLMAO:
Thats why we are here I guess. It’s to learn from others. I believe every above failure that you posted had some type of failure due to an improper installation or connection or flammable item next to exposed terminals and not a direct failure from a faulty breaker. It’s difficult to know what’s good and what isn’t good. Are we to dismiss every Chinese manufacturer? Even reputable ones? Even the newest all in ones that Will recommends are manufactured in china and aren’t UL listed and certified. Neither are our batteries.

You said that you use the T Tocas breaker for your SCC and Will recommended it as well. After doing some research, it looks like the T Tocas brand is a rebranded Gloso brand. I have both and they look identical except for the name and the breaker size. I did not break them open to compare internals though. Gloso is a world renowned breaker manufacturer and have some of the highest ratings in various breaker/auto breaker solutions. They meet the safety standards of UL, ISO, SAE, TUV, RoHS, and ENEC. I actually wouldn’t be surprised if they even manufacture the Eaton Bussman brand for them. You can find them at glosotech.com. However, I can’t find any information about T Tocas and where their manufacturing facility is located. So until I know otherwise, I’ll put the T Tocas in the same class as the Gloso brand(Cheapo+). Certain brands are notorious for their reliability and reputation and Eaton Bussman is clearly the way to go.
My inverter was rated for #1 wire and a 240Amp breaker/fuse. I went with 1/0 welding wire and 150Amp breaker option because I do not wish to push the inverter to its 3000Watt surge and don’t plan on using more than 1200 of its 1500Watt continuous output power. I will be testing that breaker though now that you’ve peaked my interest and let you know what I find. I’ll check it’s ohms and look for voltage drop and I’ll even try to trip it by running more then 150Amps thru it. All in the name of science and peace of mind. I’m going to blame you for this insanity though ?
I wonder how many people have tested their ANL and T fuses just to make sure they work?

Safety is the most important issue and not the additional cost of better quality components.
 
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