Tinbum

No, sorry, it's  you who are incorrect, look at the pylontech protocol. The protocol will send error codes for the inverter to react to. That's on top of the actual normal instructions that it sends to the inverter. eg.  by limiting the currents. (0X351 bytes, 2,3,4,5)

(That's if you have a decent inverter. I am using inverters that are over 12 years old that have no problem with Pylontech batteries. That's because they were designed properly and are a quality inverter).
It blatantly obvious that the inverts in this thread can't control the voltage correctly and that's not Pylontechs problem. They say the inverter should be approved and their is a reason for that.
 

No, sorry, it's  you who are incorrect, look at the pylontech protocol. The protocol will send error codes for the inverter to react to. That's on top of the actual normal instructions that it sends to the inverter. eg.  by limiting the currents. (0X351 bytes, 2,3,4,5)

(That's if you have a decent inverter. I am using inverters that are over 12 years old that have no problem with Pylontech batteries. That's because they were designed properly and are a quality inverter).
It blatantly obvious that the inverts in this thread can't control the voltage correctly and that's not Pylontechs problem. They say the inverter should be approved and their is a reason for that.
 

Yes the BMS is supposed to protect the battery but it seems with these inverters the inverters don't control the voltage correctly and the battery BMS is unable to turn the inverter off. Most people have no problems at all but it seems people with this inverter do. I think that says it all.

I'd change the inverter!!

After looking at your log file again its apparent the battery underwent abuse for quite a while before it died (about 3 weeks ) where the BMS had to protect itself from over-voltage and it did just that . At some point something its going to give in no matter what BMS ,if its continually being hammered with high voltage for 3 weeks probably not many will survive if i had to guess. It also experienced 61,8A charging rate on the very first day. There are plenty of people this forum that use these batteries with CAN communication with great success and that is what i would recommend you do.  Either get a new inverter that can do that or set your charging voltage and amps down and monitor extensively with something like solar assistant if a new inverter is not an option.

If I may be the devils advocate here.....
 I have seen too often where people pair one pylon 3.5kw....or lower to a 5kw or larger inverter and then cry wolf when their battery packs up and the supplier does not want to honour the claim.
Get with it guys, you must at least match the battery to the inverter,s capacity.....as a bare minimum.

You ran a single US3000C battery on a 4kw inverter ?  These batteries are only good for around 1700w each. From your log files its apparent that your charge voltage is also too high as the pack regularly went up to 54V.  Why did you not run both the US2000 and 3000C batteries?   

I dont have much knowledge on Axpert inverters but from what i remember they are known to overshoot the set charging voltage by quite a bit so you maybe want to research that and set it slightly lower. Why that never upset the US2000 i am not sure but it does seem like the newer batteries may be more sensitive to overvoltage breakdowns. So its probably the battery and inverter both to blame. 

@Grotman Yes the Axpert inverters do overshoot charge settings. I will not exceed a setting higher than 52.5 volt. This will prevent exceeding max 54.0 volt for Pylontechs. 3.5volt per cell is more than enough.

Are you sure they are Surlok their are some copies that look the same but are different? They are normally the 5.7mm.
https://www.amphenol-industrial.com/surlok-plus
https://www.amphenol-industrial.com/images/catalogs/SurLok Plus Brochure.pdf

It should be figure 2. It's to do with the cable lengths to each individual battery from the inverter. This way they are all the same so batteries should charge and discharge more evenly.

I totally agree it can be very hard re warranties, but their are 2 sides to every story. The thread we are talking about, as I said, really doesn't give enough information. The logs don't go back far enough. The problem is their from day one, of the logs shown. We can see over voltage of the pack, over voltage of individual cells, under voltage of individual cells and the SOC (0%) well below what the battery was designed for (minimum of 20% when originally sold). I don't think it's for the cell voltages that Pylontech have rejected it for, it's the overall over voltage of the pack. The pack shouldn't be reaching those voltages if the CAN is connected and working. The logs show this over voltage is not just spikes it is constant, their is a failure somewhere and it's been going on for a while, how long, we don't know as we can't see the logs. I suspect it's only the eventual failure of a cell that shows the system hasn't been working from the start. It could be said that 54v isn't really over voltage for LiPo cells but it is over voltage for the Pylontech as they designed it and it shouldn't have exceeded what the BMS asks for. (I only have C batteries so perhaps someone could confirm what  the max voltage they have seen the BMS request on the non C batteries).
Re the passive BMS this is a reference to the balancing mechanism which can either be 'passive' or 'active' it's not a reference to the protection features. Pylontech have obviously had problems with over voltage on their batteries hence the notice I attached in the other tread. When I bought mine I remember seeing clear warning messages about the initial set up and making sure the batteries didn't go over voltage. These are not like Lead acid which are forgiving.
Re being outdated. This tech is changing at a very fast pace and for the likes of HV the potential dangers are much higher and it's a much newer development. Lithium batteries have only just become common over the last few years in the settings they are now being deployed in.
I agree it is every man / woman / person for themselves. I do think their are a lot of installers, including professional ones, that really don't know what they are doing. I had a professional PV install back in 2012 and it's been an absolute nightmare.  It's been removed from the roof twice and refitted and even then they couldn't do it right, they really didn't have a clue. It's frightening when they come out with comments like 'we've always done it that way'. In the end I suggested and accepted a cash payment from the insurance company to sort it out myself. Another example is we can see installs where only one battery pack has been installed that clearly won't be up to the job, but they will still sell them and install them.
I fell out with Segen (UK) myself when I bought batteries from them. They made a mistake over shipment, corrected it but then refused to give me the discount I was entitled to. They just weren't bothered so I said I'd never use them again and I haven't. It actually worked better for me, as the next supplier I used gave me even better prices than Segen had.

I totally agree it can be very hard re warranties, but their are 2 sides to every story. The thread we are talking about, as I said, really doesn't give enough information. The logs don't go back far enough. The problem is their from day one, of the logs shown. We can see over voltage of the pack, over voltage of individual cells, under voltage of individual cells and the SOC (0%) well below what the battery was designed for (minimum of 20% when originally sold). I don't think it's for the cell voltages that Pylontech have rejected it for, it's the overall over voltage of the pack. The pack shouldn't be reaching those voltages if the CAN is connected and working. The logs show this over voltage is not just spikes it is constant, their is a failure somewhere and it's been going on for a while, how long, we don't know as we can't see the logs. I suspect it's only the eventual failure of a cell that shows the system hasn't been working from the start. It could be said that 54v isn't really over voltage for LiPo cells but it is over voltage for the Pylontech as they designed it and it shouldn't have exceeded what the BMS asks for. (I only have C batteries so perhaps someone could confirm what  the max voltage they have seen the BMS request on the non C batteries).
Re the passive BMS this is a reference to the balancing mechanism which can either be 'passive' or 'active' it's not a reference to the protection features. Pylontech have obviously had problems with over voltage on their batteries hence the notice I attached in the other tread. When I bought mine I remember seeing clear warning messages about the initial set up and making sure the batteries didn't go over voltage. These are not like Lead acid which are forgiving.
Re being outdated. This tech is changing at a very fast pace and for the likes of HV the potential dangers are much higher and it's a much newer development. Lithium batteries have only just become common over the last few years in the settings they are now being deployed in.
I agree it is every man / woman / person for themselves. I do think their are a lot of installers, including professional ones, that really don't know what they are doing. I had a professional PV install back in 2012 and it's been an absolute nightmare.  It's been removed from the roof twice and refitted and even then they couldn't do it right, they really didn't have a clue. It's frightening when they come out with comments like 'we've always done it that way'. In the end I suggested and accepted a cash payment from the insurance company to sort it out myself. Another example is we can see installs where only one battery pack has been installed that clearly won't be up to the job, but they will still sell them and install them.
I fell out with Segen (UK) myself when I bought batteries from them. They made a mistake over shipment, corrected it but then refused to give me the discount I was entitled to. They just weren't bothered so I said I'd never use them again and I haven't. It actually worked better for me, as the next supplier I used gave me even better prices than Segen had.

These 2 links will point you in the right direction.
 
 
 
Pylontech Low Voltage Battery Mornitoring and Maintenance Tool Guidance 0228_3.pdf

The charge curve shows it all. Their is very little point taking the voltage that high as you gain very very little extra capacity.
Some examples,
https://powerforum.co.za/topic/19327-best-practice-for-charging-litium-battery/#comment-168095
https://powerforum.co.za/topic/6807-guidance-requested-on-shoto-sda10-48100l5-battery-settings/#comment-154152
From the Victron web site.
Seplos BMS settings for their packs.

Here you can see the data transmitted by the Pylontech BMS to the inverter.
PYLON BMS CAN-Bus-protocol-PYLON-low-voltage-V1.2-20180408.pdf

Should be ok. If they are off they are in Idle mode.

It's pretty easy to use something like a Teensy and use it as a CAN sniffer. I use one to change the CAN messages to the inverter but also to publish readings to MQQT. You can then read in Node Red and make announcements over Alexa, publish to Pushover, e mail or Telegram for example.

You need to correct this!

That is correct placement.

A single battery wouldn't boot my Sunny island. The inverter takes a vast current on start up. Look at pre charging the capacitors in the inverter.

The batteries have a soft start and don't like surges on start up. The battery will see it as a short and shut down. I don't know your inverter so am not sure how it started last time. Is it possible it was powered up from the grid before you started the battery? Some times hitting the battery start button in quick succession may work, as when starting the second time, the capacitors in the inverter already have some charge in them from the first attempt. You could try pre-charging the capacitors first- do a search for methods, eg light bulb.
New batteries only come charged to 50% but the manual does say to recharge to min 90% every 6 months, so that's not your problem.

You need another battery really. The start up current of the inverter is too much for one battery.
 
(Batteries like to be stored at 50% SOC)

A single battery wouldn't boot my Sunny island. The inverter takes a vast current on start up. Look at pre charging the capacitors in the inverter.