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Alarm - but from where?

Alright just finished my test. I turned off the PV, ensured the MPPTs were in Snooze or off, waited 15 minutes, then fired up the inverter, and started the pool pump.
According to the victron temp sensor at the positive battery post, it was 18 degrees Celsius (64.4 F) at start of my test.
Test duration was 30 minutes before I turned everything off out of fear of fire.
I raised the variable speed pool pump to 3450 RPM right at the start.
According to the victron shunt, it was at 12.45V, 89.58 A, 1115 W during the test.
On the giandel 2000 W inverter, it has a display. The display read 12.1 VDC input, and 116 V AC, 60 Hz, 1040 W on the output side
This is very close to the 1115 W listed by the shunt.
Within 3 minutes temp sensor (TS) read 38 C (104.3 F).
The amps read 91.73 and watts read 1138, so very close to what it read 3 minutes prior except for Temp.
Within 3 more minutes - 6 total of start - it read 49 degrees C (120.2 degrees F).
Amps / volts / watts all read about the same.
Within 1 more minute - 7 total from start - it read 52 degrees C (125.6 degrees F).
Within 1 more minute - 8 from start - it read 56 degrees C (132.8 degrees F).
Within 1 more minute - 9 from start - it read 60 degrees C (140 degrees F).
Reminder: battery states charging range is allowed to be up to 122 degrees F and discharge is allowed to be at 140 degrees F, and high temp cutoff is 167 degrees F.
Got out my temp sensing gun and watched - the victron TS reads hotter than my temp sensor, so I put on my safety glasses and started monitoring with that for a while at the same time as the victron connect app over bluetooth.
Within 12 more minutes - 21 minutes from start - it read 82 degrees C (179.6 degrees F) at the TS, but with my temp gun I hit 164.4 F, and it started to smell a bit warm so measured temps everywhere I could and shut everything down.
The shunt reported 84 degrees C (183.2 degrees F).
The conductors on the positive side I'm using from the giandel were at 100 degrees F and warm to the touch.
The battery post I should not have touched, but did to ensure gun was working. It was hot - probably 150 F when I touched it. Left a mark on fingertip.
Conductor at the positive kill switch was 100 degrees F
Conductor connecting to shunt on the 'to battery' side of negative conductor was also 100 degrees F
Everything else like bus bars, fuse bar, and all other conductors were 80 degrees F or less. The connections at the inverter were even colder - closer to 75 degrees F.

If the victron temp sensor is supposed to warn or alert when at 120 degrees F, why didn't it?
If the victron temp sensor is accurately reporting 183.2 degrees F, why didn't the battery's BMS shut down at 167 degrees F?
Upload pictures in a minute - will also get VRM back online to get some reports.
 
Seems that maybe some data was lost when I turned off the inverter, then killed the battery. Maybe it is just delayed in VRM.
Says shunt temp hit 169 F, and that current was 93.80 A. That is lower than the screenshots I took of victron connect and my temp gun, so I assume data is averaging or delayed or lost.
Will upload the pix from phone.
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Here’s the evidence.
Going to watch Will's review again of Chins battery.
Edit - the uploads went in a strange order, but bottom line is you can see the smart shunt did track that temp got that high if VRM did not/has not.
 

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Tomorrow, I will replace the double-red 5 AWG conductor provided by giandel with the re-crimped conductor I re-created. I will then let the sun charge the battery to 100% SOC - unless its like today and cloudy and doesn't quite make it. I will then re-perform this same test in identical fashion, and report back findings.
I am fairly certain that - despite some feedback to the contrary - that the issue exists only the positive battery post on my battery, and may be heat transferring from the opposite side of the battery post inside the battery, presumably the P+ wire from the BMS.
I am also thinking that this BMS does prefer 40 A constant, and is not a huge fan of 50 A constant or more, and really doesn't love 100 A constant when charging. That's fine - going to 48 V eventually - and this system will be used for smaller loads in the future. That is - if it isn't seriously damaged or anything. The puzzling thing to me is why does only the positive post get hot, and the negative does not.
Here's a random thought - what if I replace the bolt being used to hold the lug to the battery post? They both match. I really think that the underside of the battery top plate probably has a much smaller conductor than AWG 1, and so the heat is going there. But why not to the negative side. Hmmm.
 
I’d say there’s something up with the internal connection of the positive terminal.

Remember the positive terminal should just be a conductor from the terminal to a cell. The BMS connects to the negative lead.
 
I’d say there’s something up with the internal connection of the positive terminal.

Remember the positive terminal should just be a conductor from the terminal to a cell. The BMS connects to the negative lead.
yes that is what I am seeing on 2-3 of wills chins video reviews.
Will continue to do my testing, while awaiting the documentation from enjoybot/chins/litime/ampereTime on what their BMS actually supports.
Starting to feel like I'm just overloading it.
No one else chiming in to say that yes, my amps are too high to continuously run the inverter/pump/heater.
Otherwise this is a great review of the battery since it never seems to stop working.
Also Will determined that there was overtemp charge protection...he was pushing 10 A into battery then dunked the test lead into ice cold water and the bms would disconnect/not allow any further charging. My situation is on the discharge side. And I'm thinking that there's nothing that will stop me from continuing to discharge - the BMS won't stop if I did 200 A is my guess. Not that I'm going to.

I am considering/budgeting for future...perhaps I will tear into the battery and pull the cells and build a DIY battery with a Daly bms like will did in a milk crate or something. that way I could at least connect to battery with bluetooth and see what's going on, if anything.

In the will videos, I do see that the leads inside the batteries are hydraulicly crimped he said, and the conductors they use don't look particularly beefy in any way. I think the conductor I'm using now outside the battery looks bigger than the ones inside the battery he shows in his videos.
 
I have heard back from the battery manufacturer.
Apparently they shipped some with 100 A BMS, and others with a 200 A BMS. The label outside did not change. Their distributors may have updated their web sites with the incorrect information or something like that. They have eBay and Amazon stores.

For 100BMS they recommend no higher than 50A continuous. The max is 100A. They recommend using 4AWM cable.

For 200BMS they recommend no more than 100A continuous. The max is 200A. They recommend using 2AWM cable.

They also noted that their batteries will automatically enter the protection state when the temperature is higher than 90°. Normally the battery discharge temperature is -20°-60°. I am asking if that is Fahrenheit or Celsius.

They also said that it is normal for the temperature of the positive and negative terminals to rise during the use of the battery.

As a reminder I am using 1 gauge 1AWG. My new hydraulic crimper arrives today.
 
so, there is no way to tell which BMS you have without pushing over the limit and testing and seeing where it goes to protection... or fries if something isn't right - Brilliant
 
A 100a BMS should have no issues discharging at 100a. You are noticing the terminal is getting warm at 80a, there is zero chance there is a BMS sensor on the terminal.

The sensors are on the cells themselves.

I feel you have a terminal wiring issue causing the heat, the BMS protection won’t catch it until it’s much too hot.

So either you know you can’t exceed 50a or request a RMA.
 
A 100a BMS should have no issues discharging at 100a. You are noticing the terminal is getting warm at 80a, there is zero chance there is a BMS sensor on the terminal.

The sensors are on the cells themselves.

I feel you have a terminal wiring issue causing the heat, the BMS protection won’t catch it until it’s much too hot.

So either you know you can’t exceed 50a or request a RMA.
I have gotten it to 95A constant as you may recall - when it is about 40 minutes in it is quite warm to the touch. Never had the internal BMS shut off the battery due to overcurrent charging or discharging. Just that positive conductor gets toasty. I have 2 cameras pointing at it right now, and keep the VRM open to realtime during the day when I am running the pump and charging.

This is my least favorite time of day for looking at VRM, however. I cannot easily see what the load is actually requiring. Probably 30 A right now, but the PV is providing 1.3A from victron 100/20, but the 'dc power' says 2.9 A. I will be adding the second shunt to the FM 80 MPPT later tonight. VRM should look a bit different tomorrow. Awaiting the arrival of my hydraulic crimper and lugs. PV is likely doing about 400 watts right now.

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I wonder if there is a loose connection on the underside of the positive post causing heating... something to think about after recrimping the wires
 
I wonder if there is a loose connection on the underside of the positive post causing heating... something to think about after recrimping the wires
yes planning a trip to get a multi-tool to cut open the battery next week should I not figure this out. I feel that is coming. A bit nervous, but can watch Will's video where he did the same thing to the 100 Ah battery, wear an aspirator and eye protection, do it far away from anything with cordless tool, tread lightly, work slowly, wear gloves, etc.
The manufacturer told me, however, that there were the two versions - 100 A and 200 A. If it is a 100 A that I have, and it is rated at 50 A continuous, then no wonder it is warming up when I run 94 A continuously as the temp rises and rises.
I like the idea of removing the battery temp sensor for the next test, though. That is what @sunshine_eggo had suggested I do a second time.
If it turns out I spent all this time and effort to replace lugs and crimps and shrink wrap and now conductors and a new crimper to fix conductors/lugs, and the battery still heats up, I'll consider:
Option 1 - opening up the battery, inspecting the cells, and get a 200 A BMS and milk crate.
Option 2 - just move it to my other setup as a standalone and never run more than 50 A discharge or charge through it sustained just the way it is, saving time and money.
Either option will also force my hand to go to 48V setup faster.
If it doesn't heat up with the victron temp sensor removed, with these same conductors I have right now, that will be a surprising plot twist as well. I will test that later tonight.
 
It would be 100A discharge, 50a charge

And again that’s internal to the BMS electronics, not conductor/terminal limitation.

Unless they know they have a whole bad batch and say it’s 50a charging or discharging due to the heat yours seeing from a bad terminal connection.
 
It would be 100A discharge, 50a charge

And again that’s internal to the BMS electronics, not conductor/terminal limitation.

Unless they know they have a whole bad batch and say it’s 50a charging or discharging due to the heat yours seeing from a bad terminal connection.
Oh interesting. They said continuous discharge for 100BMS was 50A. I didn't ask about continuous charging. You thinking it should be 100A discharge continuously and 50A charge for the 100BMS or the 200BMS?
 
You have that in an email you could screen shot?

I’ve never hear of 100a BMS limited to 50a for discharge.

IMO review the listing of the item that you bought and if they are stating the the specs are now different, I’d demand a replacement.
 
You have that in an email you could screen shot?

I’ve never hear of 100a BMS limited to 50a for discharge.

IMO review the listing of the item that you bought and if they are stating the the specs are now different, I’d demand a replacement.
photos might not be in order from emails - there's a lot of back and forth and we both have long email signatures.
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Looks like confusion on their end, they initially stated max continuous discharge 100a then stated 50a discharge (might have meant 50a charge).
 
Or they cut corners and put a 50 amps bms in with 100amp surge...

I am voting for loose wire on the underside of the positive post
...or the bms is at that end and the heat adds.
 
Or they cut corners and put a 50 amps bms in with 100amp surge...

I am voting for loose wire on the underside of the positive post
...or the bms is at that end and the heat adds.
at a crossroads. Don't have another 200Ah 12V battery. Don't have a BMS to replace this one if I wanted to and throw into a crate. Don't have the 48V battery yet to install the quatro and ditch the Giandel inverter and Chins battery. Don't have a multi tool to cut open the battery. Open to suggestions. would like to avoid any downtime. A day is fine, though. All costs money no matter which way I go. If I don't cut open battery, I save money and can use the battery for smaller setup only and never get close to 50 A continuous discharge or over 20 A charge. Open to suggestions.
 
Alright @robbob2112 @ricardocello and @sunshine_eggo - some updates on this thread. As a quick recap, I have a chins 12 V 200 amp power battery. A whole bunch of Victron equipment connected to it. I was getting dangerously high readings at the positive battery post only not the negative. No other place in the system was hot. I got a replacement BMS from JBD that took seven weeks to arrive. I removed the battery and carefully cut it open, Having watched Will do it 30 times now. Used proper safety protections. I had my wife do it while I stood nearby with a fire extinguisher lol. We removed the old BMS that had a sticker on it and little else. The sticker was quite faded and red 2021. We replaced all the wires for the balance leads, of course, and created new positive conductors and negative conductors and the leads from the battery bank to the BMS. We connected a charger and it has charged backed up to 100% state of charged and is balanced. We did that on the bench because we didn’t want to install it until we knew it would at least charge. We have not tried any discharging yet. My wife noticed something peculiar about the conductors that came with the chin‘s battery. We cut apart the positive lead and noticed that it was aluminum wire. Then we also cut open the leads between the cells and the BMS, and they were all aluminum. Then we could open the wires between the BMS and the Posts on the battery case, and noticed they also are aluminum.

Pictures are attached.

I don’t know that it says anywhere with the wires can’t be or won’t be aluminum, but I expected them to at least be copper. I am certain they are not tinned copper marine grade stuff.

I have thrown away all the aluminum wires that it came with.

Although I paid around $80 for this BMS with shipping that I just received, part of me wonders if I couldn’t have reused the one that came with just with copper wires.

I think the BMS it came with was designed for 50 A continuous maximum.

I will be testing the pack tomorrow and will report back my findings. I would be very surprised if the temperature sensor reports back an over temp condition. I will also now be able to connect to the new JBD BMS with my Bluetooth, which I was not able to do before with the one that came with the CHINS battery.

For months, I have had a ton of solar panels and solar charge controllers that I have had to program to never exceed 50 A output total. I could also never run my loads for more than an hour without causing an over temp condition. Fingers crossed that this solves the problem.
 

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Triple 8awg for the negative, and dual 6 for the positive, interesting

So for the positive connection, single lug on the case terminal and dual lugs on the cells?

When you undid the case terminal how tight was the bolt? If that was the source of the heat it should have been a little loose.

Best of luck it should handle 100a without even getting warm to the touch.
 

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