Breaker tripping prevent full days charge

[mikefitz]

But the 250A sizing seems high in my (in)experience.

With 2AWG perhaps better to use 200A fuses.. I guess the BMS is rated for 200 amps maximum.

Do I need to get second set of Busbars. One set for paralleling the batteries, second set for Loads with a shut off switch in-between so I can completely isolate my batteries?

A second set of buss bars would be a good idea. It's a big battery bank at 12 volts. What is the expected load current ?
If high amps you will need a quality isolation switch, consider the BlueSea range.

 

[SirEbrawl]

Here's today's breaker Trip graphs.

 

[SirEbrawl]

With 2AWG perhaps better to use 200A fuses.. I guess the BMS is rated for 200 amps maximum.


A second set of buss bars would be a good idea. It's a big battery bank at 12 volts. What is the expected load current ?
If high amps you will need a quality isolation switch, consider the BlueSea range.

Main Load will be AirConditioning, here are it's load specs.

 

[SirEbrawl]

Energy being delivered by the controller has nowhere to go. Controller cannot respond fast enough.

Shunt in not connected corectly as a battery monitor.
View attachment 224702

Connect the shunt correctly and replace the crap breakers with fuses or Bluesea/Bussmann breakers.

Add a MRBF 250 amp fuse in a Blue Sea fuse holder on each battery positive.

Worth the extra $$ for the Buss version?

 

[Mattb4]

Sorry to not follow this for awhile. These breakers you are selecting are not really designed for higher voltage DC operation. Your panels in 3S will be potentially outputting 66vDC.

I would suggest a Westinghouse Dinrail style good for 125vDC. 2 pole for complete isolation of your panels.

 

[outboard1196]

Sorry to not follow this for awhile. These breakers you are selecting are not really designed for higher voltage DC operation. Your panels in 3S will be potentially outputting 66vDC.

I would suggest a Westinghouse Dinrail style good for 125vDC. 2 pole for complete isolation of your panels.

I believe the breaker in question is after the charge controller and the battery bank is 12v .
The blue sea / bussmann breaker should be rated up to 24v I believe .

 

[Mattb4]

I believe the breaker in question is after the charge controller and the battery bank is 12v .
The blue sea / bussmann breaker should be rated up to 24v I believe .

Ahh I see the 120a rating. For this you would likely want to go to a MCCB or one of Midnites offerings. The one on the PV line could be the Westinghouse fro the higher PV voltages.

 

[wpns]

Shunt in not connected corectly as a battery monitor.


Connect the shunt correctly and replace the crap breakers with fuses or Bluesea/Bussmann breakers

This!

 

[mikefitz]

With the controller, select the lithium option. In the battery set up field select preset and then select the lithium option.
This will give a absorbtion voltage of 14.2 and a float of 13.5. The selection you have is producing too high a voltage and may cause BMS shutdown of the charge path.
BlueSea breakers are usually rebrand Bussmann.

 

[outboard1196]

Sorry to not follow this for awhile. These breakers you are selecting are not really designed for higher voltage DC operation. Your panels in 3S will be potentially outputting 66vDC.

I would suggest a Westinghouse Dinrail style good for 125vDC. 2 pole for complete isolation of your panels.

View attachment 224772

Although it wasn't an issue looks like the breaker for PV side is the same style as battery side and should be checked to make sure its rated for the task . the breaker may be redundant and not needed due to the panel fuses but I'm not an expert .

 

[SirEbrawl]

BlueSea breakers are usually rebrand Bussmann.

The two breakers I show are both BlueSea, 7188 285-series (magnetic/hydraulic) and 7146 187-series (thermal). ChatGPT suggests the magnetic/hydraulic mechanism for a Van setting where vibrations can cause 'nuisance trips' in the thermal mechanisms.

 

[SirEbrawl]

Although it wasn't an issue looks like the breaker for PV side is the same style as battery side and should be checked to make sure its rated for the task . the breaker may be redundant and not needed due to the panel fuses but I'm not an expert .

yes both the 120A (SCC/battery) and 30A (solar/SCC) are M1A4 brand. though the 30A hasn't tripped yet, which doesn't mean it's necessarily working correctly for the time being.

 

[740GLE]

Close-up of tripping breakers connections. zero play, copper washers as well.View attachment 224742

Ask charGTP if those lugs are proper sized . . .


Personally I’d opt for fuses, quality ANL, or mega fuses is all you need for a 12v system.

Where did you get your cables from? Did you make them yourself or we’re they premade

 

[740GLE]

View attachment 224747View attachment 224748View attachment 224749View attachment 224750
After VE linking, they Battery Voltages seem in sync.The biggest difference (lag) observed is 0.04V which I assume is 'negligible'?

Is it possible that lack of VE communications could have been causing the breaker trip? I just moved the Van out of shade, but intermittent cloud cover. Will update how it performed later today.

'Dial back the charge current': I want to make sure I'm adjust the correct setting...View attachment 224751 Also is 'BatteryLife' the ideal setting?

Looks like you are tripping at only 30a, set that 100a for 20a, but again this is a band aid until you fix those lugs and connections from SCC to battery/bus bar.

 

[SirEbrawl]

Where did you get your cables from? Did you make them yourself or we’re they premade. set that 100a for 20a

I made them with WindyNation 2AWG, 2AWG-3/4 lugs and Pittsburgh 8 ton hydraulic wire crimping tool. ChatGPT agreed that partial heating of the lugs could be causing the trip.

OK to 20a max, will post results after but it's already 1pm here

 

[LydMekk]

Did you really consult chatgpt AI? LOL

 

[740GLE]

I consulted chatgpt what I should have for lunch, I over rode its recommendations and ate leftovers

 

[740GLE]

I made them with WindyNation 2AWG, 2AWG-3/4 lugs and Pittsburgh 8 ton hydraulic wire crimping tool. ChatGPT agreed that partial heating of the lugs could be causing the trip.

OK to 20a max, will post results after but it's already 1pm here

3/4” lugs? Or 3/8”? Yeah that’s a bit large. Least you can make your own.

 

[SirEbrawl]

Did you really consult chatgpt AI? LOL

Yes, when learning new things I always use ChatGPT to get an overview of a subject. Obviously I don't take it as gospel and cross-check the information with experienced people like this Forum. I also cross-check it by asking the same questions multiple ways and play devils advocate to check its confidence. After all it's drawing its conclusions from forums like this one.

 

[SirEbrawl]

Looks like you are tripping at only 30a, set that 100a for 20a, but again this is a band aid until you fix those lugs and connections from SCC to battery/bus bar.

So 25A got an hour absorption with no trips, 30A also got an hour. 40A instantly tripped the 120A breaker. Checking if 35A gets through

 

[SirEbrawl]

3/4” lugs? Or 3/8”? Yeah that’s a bit large. Least you can make your own.

excuse me, yes 3/8.

Here are some Temperature Reads. Note ambient in outside is 97F, inside van 109-115F. The 'In' lug reads +10-20F higher than the 'Out' lug. And the contact point is about +5F higher than rest of lug. It trips at +142F.

 

[740GLE]

All good info, but better info would be hearing you either retermintated those cables with proper lugs or ordered a fuse/fuse holder with 3/8 bolts and toss the breakers in the trash.

I fear you found the wrong solution, dialing back the charge current to avoid a trip and will just let the system work and forget you have an issue that needs to be addressed. Especially if the breaker is at say 130-140f and not tripping, that’s just begging for trouble.

Also those thermal IR guns work as a rough guesstimate/average but don’t give resolution for small hot spots.

 

[outboard1196]

30A should not heat up a 2awg cable, crimp or breaker that much .
Shake hands with danger .

 

[Kiwi2000]

A lot of us, myself included, started out with breakers like those. It naturally seemed like a good idea to have a switch and a resettable fuse rolled into one unit.

However most of us learn pretty early on that those breakers soon become the weakest link in the system once we start using higher amps more consistently. The internals of those things are simply too flimsy to handle high amps continuously. Most of my problems went away when I got rid of them and used dedicated switches and fuses separately.

 

[SirEbrawl]

Yes, Im not expecting to leave this breaker in place

All good info, but better info would be hearing you either retermintated those cables with proper lugs or ordered a fuse/fuse holder with 3/8 bolts and toss the breakers in the trash.

I fear you found the wrong solution, dialing back the charge current to avoid a trip and will just let the system work and forget you have an issue that needs to be addressed. Especially if the breaker is at say 130-140f and not tripping, that’s just begging for trouble.

Also those thermal IR guns work as a rough guesstimate/average but don’t give resolution for small hot spots.

Yes, was just troubleshooting further to see if any other issues became clear.

Just need to decide on the new breaker.

Some of you suggest fuses over breakers. Now this Trashy M1A4 is a Thermal breaker. I was planning to replace it with the BlueSea, 7188 285-series (magnetic/hydraulic) breaker. Do you still suggest a fuse over this high end Magnetic/Hydraulic breaker?