Is this MCCB correct

[Ahjwinth]

Hi, I want to purchase a MCCB for my 16s 280ah battery bank to have a protection but also a switch to isolate the battery bank.
I live in the netherlands and struggle to find a shop in europe that sells 125A DC breakers for a reasonable price. Since this is a essential piece of safety equipment I prefer to use one of the major brands and not shop on Aliexpress. I work for a US company and therefore also working sometimes with US manufactured battery chargers from ABC, American Battery chargers and we never head issues with the Carling Technolgies breakers and therefore I would prefer to purchase these. I found them on Ebay but not 100% sure if they are correct for the application.
Here is the advertisement on ebay:https://www.ebay.com/itm/284466531975?hash=item423b86ce87:g:trQAAOSwRKVhUO0m
Carling Technologies 125A DC 2-Pole Circuit Breaker EA2-B2-14-912-22A-BC.

When I look in the spec sheet from carling for the specific model there is a note behind the specific amp rating of 125A. For me it is unclear what they mean with this. Does someone know if this CB will function to open when current is to high or do they mean it is a switch only and it doesn't have a protection function?
25 A rating (Code 912) available as a Switch Only (Circuit Code A), rated 125 VDC (Code B).

 

[koppted]

Carling is high quality stuff. The only thing that bothers me about their type of breakers is that the connection points are on the posterior of the unit and they are nut and bolt connections. Most present a nightmare if you want to actually mount this in a box. Btw this is not an MCCB form factor, unless its definition is malleable.

 

[Bud Martin]

Here is the explanation for '4 circuit'
125 A rating (#7 Current rating: Code 912) available as a Switch Only (#4 Circuit: Code A), rated 125 VDC (#11 Maximum Application rating: Code B 125VDC/120A).
So it is a heavy-duty switch with 125A current rating and 125VDC rating.

https://www.carlingtech.com/circuit-protection-circuit

Switch Only​

The Switch Only circuit is the same as a Series Trip, but without a sensing coil. It functions as a low cost, heavy-duty switch when overload protection is not needed. The Switch Only configuration is available with and without an auxiliary switch.

circuit_switch_only.jpg​

 

[Ahjwinth]

Thanks for the feedback and clarification. So this breaker Is not what I’m looking for. I will continue to search if I can purchase a good quality MCCB at a reasonable cost.

 

[koppted]

Thanks for the feedback and clarification. So this breaker Is not what I’m looking for. I will continue to search if I can purchase a good quality MCCB at a reasonable cost.

MCCB's are super expensive if you buy the brand new but I would check ebay for "Open Box" ones that have never been energized for a good bargain.
here is a good example of one that would cost in the 1000's if bought new https://www.ebay.com/itm/164054974692
This one has a "micrologic" adjustment were you have have it trip at a lower current if you want it to. But even at $600 plus i'd rather have a T-class fuse in the mean time. If I ever see it for $100 I'll jump on it.

 

[oc_geek]

Thanks for the feedback and clarification. So this breaker Is not what I’m looking for. I will continue to search if I can purchase a good quality MCCB at a reasonable cost.

I'm in the same spot as you.
I only find super-uber expensive (and 3 pole) MCCB in Europe... Shnider has (had) one 2P (pretty exp too) which is going to be discontinued in May...
...an the Ali counterparts like this... 2P 125A MCCB i'm not sure to trust..

Had you managed to find something ?
Thanks

 

[HRTKD]

Midnite Solar has some larger amp circuit breakers. There is a forum member that is using one in the position you're looking at. They could be rebranded Carling units, I have no idea.

 

[rhino]

If you need more than one pole and/or higher then 250A which is the highest Midnite Solar provides you can see if you can get ahold of MCCB made by Noark which are much cheaper then the other brands new.

 

[oc_geek]

..in EUROPE thought..

 

[Ahjwinth]

I'm in the same spot as you.
I only find super-uber expensive (and 3 pole) MCCB in Europe... Shnider has (had) one 2P (pretty exp too) which is going to be discontinued in May...
...an the Ali counterparts like this... 2P 125A MCCB i'm not sure to trust..

Had you managed to find something ?
Thanks

Hi, I stopped my search for an DC MCCB and used fuses instead.

 

[Pulith]

Hi,
I have an mccb which is in between my battery pack and hybrid inverter. When I am tring to use my hotwater the mccb keeps tripping from inside. The lever don't fall but it's trip bcz I get an error on my inverter.
Inverter is 5000W
Mccb 250A
Hot water is 3500W.

Also I noticed if I on 2 air conditions also this happens. Even when both airconditions are on both together would pull about 2500W.

But this don't trip is there is solar I think bcz then solar would also be giving some electricity directly.

I am sure there is no way that the inveter is pulling 250A for the mccb to trip. I 1st had a 160A so since it was giving me trouble I changed to the 250A to see if the problem would get solved but it didn't.

 

[HRTKD]

If this is a 12 volt system then a 3500 watt load would certainly exceed 250 amps.

Size the breaker to 1.25 times the nominal load. This also assumes that your cabling can support the load. A cable that is too small will contribute to the breaker tripping.

 

[Pulith]

If this is a 12 volt system then a 3500 watt load would certainly exceed 250 amps.

Size the breaker to 1.25 times the nominal load. This also assumes that your cabling can support the load. A cable that is too small will contribute to the breaker tripping.

No it's a 48V. Wire size is 35mm

 

[HRTKD]

Post a link to the breaker. Please provide as much information as you can. You'll get better answers when there is enough information.

 

[Pulith]

Inverter is programmed to change if pull from battery pack is over 150A but it don't change.when the load is on my ac side amps shows 15.2A @240v so that's about 3,648W so if I convert that to dc it's about (3648/48) x 1.25 x 1.25 = 118.75A dc with all ineffecency.

 

[HRTKD]

That breaker is marketed for PV. It doesn't seem to be for between a battery and inverter. Plus, I can't find that breaker anywhere except on AliExpress, which should be a red flag.

Maybe it's an OK breaker, maybe it isn't. Since you're operating it well under the specs, that makes me question the quality of that breaker. Most of us are using a Class T fuse for between the battery and the rest of the system. That's not to say that you can't use a breaker in that position but I sure as heck wouldn't be using a $30 breaker. I would expect a breaker for that position to cost closer to $100.

For those that are more experienced with breakers, here's the page on AliExpress:

https://www.aliexpress.com/i/2255800968261432.html?gatewayAdapt=4itemAdapt

 

[Pulith]

I tried toman mccb but that was 160A gave the same result. I do have a fuse 250A. Not sure if it's a class T fuse though.

 

[HRTKD]

No, that's a MEGA fuse. It says right on top of the fuse.

This is a Class T fuse:

Class T Fuses - Blue Sea Systems

Use with Class T Fuse Blocks for circuit protection of devices including inverters. high interrupt capacity for large battery banks including Lithium-ion and TPPL batteries.

www.bluesea.com

Since you're tripping a 250 amp breaker and a 160 amp breaker, I would start checking the system for connection issues. I would not switch to a fuse until you verified that the system is wired properly.

What is the distance between the battery and inverter?

 

[Pulith]

I hv a cable 35mm from battery pack to inverter its 4mts long. I kept it long so that I can move the pack when I want.

 

[HRTKD]

For the distance, amperage and voltage, your 35mm cable (~2 awg) should be just fine.

As I said before, tripping a 250 amp breaker should be a red flag that something is wrong with your system. With the system under load, check every connection and cable for heat. Any spot that is hotter than everywhere else needs to be addressed.