Breaker for Battery bank
- Thread starter latinhawk
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FilterGuy
Solar Engineering Consultant - EG4 and Consumers
Are you looking for a breaker to put on each battery or a breaker for the combined battery bank?
What trip current do you need?
A few of my thoughts:
When I first got into solar, I wanted breakers everywhere. I viewed fuses as inconvenient and old-school. However, I have changed my mind on that.
What trip current do you need?
A few of my thoughts:
- Stick with a name brand. You can find a lot of cheap breakers that are more of a hazard device than a safety device.
- The breaker must be bi-directional. Unidirectional breakers have a nasty characteristic of catching fire if they are manually opened when the current is running in the wrong direction. (Not to mention that they don't trip for over-current in the wrong direction)
- The breaker must have a very high interrupt rating. (This is different than the trip rating)
- Above ~150 Amps, good DC breakers start to get very expensive.
When I first got into solar, I wanted breakers everywhere. I viewed fuses as inconvenient and old-school. However, I have changed my mind on that.
- If a 100A+ breaker or fuse blows, either the design is very poor or something catastrophic happened. Either way, the system should not be turned back on till the issue is understood and resolved.
- Fuses are more reliable than breakers
- Fuses are cheaper than breakers unless you keep blowing them....but see point 1
- In most cases, high-current fuses are easier to mount than high-current breakers.
BentleyJ
Solar Wizard
Midnight Solar has 125A, 175A and 250A non polarized DC breakers with and without remote trip option. The breaker is actually a Carling Technologies type F.
Schneider also makes a good DC breaker that they use for the Power Distribution Panels sold as accessories for their inverters.
Schneider also makes a good DC breaker that they use for the Power Distribution Panels sold as accessories for their inverters.
As filterguy was alluding to, the interrupt rating is why many of us use fuses, more specifically, class t fuses for the battery bank. They work, and the cost is reasonable DonRowe class t fuse
Any appropriately rated change-over switch would do the job.
There are plenty of purpose made switches sold for the purpose. Typically, battery isolator switches offer Off, A, B, A+B input options.
They are commonly used on trucks and boats if you are looking for a local stockist.
There are plenty of purpose made switches sold for the purpose. Typically, battery isolator switches offer Off, A, B, A+B input options.
They are commonly used on trucks and boats if you are looking for a local stockist.
PreppenWolf
Solar Wizard
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600A?
600A at 54V is 34kW.
Why are you switching power between 34kW supplies?
600A at 54V is 34kW.
Why are you switching power between 34kW supplies?
PunchySunshine
Solar Enthusiast
Eg4 LL Guidance
Hi, I am gathering materials to complete a 120v off grid solar system for my small cabin and have many questions that I hope the community can help with. I worked with Lori at practical preppers and got as much as I could they had to offer for my setup. My system will comprise of 3 EG4 LL 48v...
diysolarforum.com
I put one on each + for each inverter after the bus bar. Both of them into a box. Worked out OK.
John Frum
Tell me your problems
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6000 ac watts / .85 conversion factor / 48 volts low cutoff = 147.058823529 inverter amps
147.058823529 inverter amps / .8 fuse headroom = 183.823529412 fuse amps
FilterGuy
Solar Engineering Consultant - EG4 and Consumers
OzSolar
Whatever you did, that's what you planned.
OzSolar
Whatever you did, that's what you planned.
I believe these 2 pole
Is there such a thing a panel mount adapter to <something handy> kit? It's that or buy an DC load center which seem pretty pricey for no more than they are.
Carling Technologies 125A DC 2-Pole Circuit Breaker EA2-B2-14-912-22A-BC Aux Sw | eBay
Find many great new & used options and get the best deals for Carling Technologies 125A DC 2-Pole Circuit Breaker EA2-B2-14-912-22A-BC Aux Sw at the best online prices at eBay! Free shipping for many products!
www.ebay.com
edit to fix typos (that just needs to be in my signature line...
)
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Maybe but probably not.
Rules are great, but context counts for something too.
Good luck finding a 183.823529412 A fuse
A 200A fuse might be easier to come by!
Bluesea makes some of the best quality equipment out there but most of their stuff is rated for 32v and below when it comes to battery switches.
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It depends on the max draw your inverter is capable of.
But don't forget to put a Class T fuse close to your battery bank for protection.
John Frum
Tell me your problems
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That disco switch is only rated to 32 volts.
Prince Of Darkness
New Member
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- Jun 20, 2022
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Hi Oz..,I believe these 2 pole remote trip will suit this need but one still has to come up with a way to install them since they are panel mount style. No need for the remote trip but the price is right. I just bought one for my new Victron 450/100 charge controller to go into my Outback DC load center. It arrived brand new and as decribed.
Is there such a thing a panel mount adapter to <something handy> kit? It's that or buy an DC load center which seem pretty pricey for no more than they are.
Carling Technologies 125A DC 2-Pole Circuit Breaker EA2-B2-14-912-22A-BC Aux Sw | eBay
Find many great new & used options and get the best deals for Carling Technologies 125A DC 2-Pole Circuit Breaker EA2-B2-14-912-22A-BC Aux Sw at the best online prices at eBay! Free shipping for many products!www.ebay.com
edit to fix typos (that just needs to be in my signature line...
Good that you do not need Remote Trip, as, the extra terminals on the rear are an Aux Switch, which, I believve, indicates weather this breaker is Open. or Closed, IIRC.
A good find, though. BTW, think in the Wind-Sun store, the Schneider 125 A Panel Mt breaker (without RT) is very inexpensive.:
Schneider Electric 865-DCBRK-125 125 Amp DC Breaker
Schneider Electric 865-DCBRK-125 125 Amp DC Breaker
www.solar-electric.com
This may be SE closing them out. Am a real MN fan, but, this breaker seems like a deal FWIW, etc, Luke
OzSolar
Whatever you did, that's what you planned.
I don't think Blue Seas has anything rated for use over 48v. And they really mean a max of 48v, not 48v nominal, per a conversation I had with thier tech support a while back.
OzSolar
Whatever you did, that's what you planned.
Thanks for pointing that out! I'll correct that. Honestly I just glanced at them and promptly made an incorrect assumption.
Prince Of Darkness
New Member
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To cloud the waters, a bit more, the Wind-Sun 125A breaker might not be supplied by SE, as elsewhere, a breaker with the SE number, appears to be rated at 100 A carry, 125A Trip, and has front-facing screw terminals, whereas the W-S one appears to be different:
As you know, the MN breakers carry the rated current indefinetely, and trip about 20% higher current, in a bit of time:
FWIW, YMMV, etc Luke
Schneider Electric 865-DCBRK-125 - Inverter Supply
Shop for Schneider Electric 865-DCBRK-125 at Inverter Supply for best prices online. Schneider Electric 865-DCBRK-125, Schneider Electric, 865-DCBRK-125, 125 Amp Panel Mount Breaker 125 VDC; (1 - Pole 26 mm), Schneider Accessories
www.invertersupply.com
As you know, the MN breakers carry the rated current indefinetely, and trip about 20% higher current, in a bit of time:
FWIW, YMMV, etc Luke
You are absolutely correct...good catch!!
I did the math and it works for my 48v system based on my amp draw.
But, I should not have put it up here as an option. I will edit my post to delete it.
Ok, here I go again. I found selector switch on ebay advertised as 12v-48v 600a. I ordered it and got it today. However, it says on the selector dial only up to 32v.
My question is, can I use it in my 48v system? I thought it was a great find because al others advertised at 32v and I haven't found anything rated 48v.
My question is, can I use it in my 48v system? I thought it was a great find because al others advertised at 32v and I haven't found anything rated 48v.
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