question

Javier Pardo avatar image
Javier Pardo asked

Pylontech US2000B + Pylontech US2000C high voltage alarm

Hello, I have been installing a Victron Quattro for a few months with a set of 6 Pylontech batteries, model US2000B. Everything has worked perfectly during these months.

Two days ago I added 6 new Pylontech model US2000C batteries to the set for a total of 12 batteries.

The installation is carried out as recommended by Pylontech, that is, the master battery is a US2000C, from the second to the seventh they are US2000B and from the eighth to the twelfth US2000C.

Yesterday I had the system working without problem, the batteries charged up to 100% and then discharged overnight up to 25% as usual.

But right now a high voltage warning has just arrived when they have reached 98% charge.


The notice clears every minute and reappears again.


At least 10 notices have already arrived.


I do not know what I can do.


Any recommendation? I don't know what to do and I'm a little scared by this.


Thanks in advance.


Update 1: The battery now indicates that it is at 100%. It seems that the alarms have stopped, but I don't really understand what is happening or if there is something that is not working correctly. Could someone give me any indication? Thank you.

2021-04-29-18h49-41.jpg

Update 2: Attached my charger settings, if that helps.

screenshot-20210429-191420.jpgscreenshot-20210429-191441.jpg


Notes:

- Quattro firmware version is 430

- MPPT chargers version is 3.02

2021-04-29-18h41-20.jpg


2021-04-29-18h39-46.jpg


Pylontech
2021-04-29-18h39-46.jpg (50.2 KiB)
2021-04-29-18h41-20.jpg (34.7 KiB)
2021-04-29-18h49-41.jpg (42.3 KiB)
screenshot-20210429-191420.jpg (81.6 KiB)
screenshot-20210429-191441.jpg (133.4 KiB)
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

2 Answers
seb71 avatar image
seb71 answered ·

Probably the new batteries have cells which are not yet balanced (equal state of charge/equal voltage when fully charged).

You can temporarily lower the charging voltages and also maybe decrease the maximum charging current.

5 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Javier Pardo avatar image Javier Pardo commented ·

Hi @Seb71, thanks for your kindly reply.


What I do not understand is that yesterday the system was working wonderfully, as I said, loading to 100% without giving any kind of alarm.

Is it normal this alarm occur today?


On the other hand, you speak of modifying the charging voltages, but what would then be the indicated values that I should put? and what would be the best way to do this?


I would not like to create more problems so I would appreciate timely indications to be able to carry out the steps to solve the problem.


Thank you very much in advance.

0 Likes 0 ·
seb71 avatar image seb71 Javier Pardo commented ·

Maybe my answers from this thread would help.

0 Likes 0 ·
Javier Pardo avatar image Javier Pardo seb71 commented ·

Thanks again @seb71


I see that this is a common problem on newer systems. As I mentioned previously, I have been using the Pylontech US2000B batteries for several months without any problem and that is why I was a little scared to see that this happened now after having installed the new US2000C to battery pack.


I understand that over time (hopefully a few days) these messages will disappear and all batteries will balance out.


My question now comes to know if it is necessary to update the firmware of any of my devices or I can be sure that this is not the problem.


Thank you.

0 Likes 0 ·
seb71 avatar image seb71 Javier Pardo commented ·

I think in your case the issue is cell inbalance.


I like to keep the firmware up to date, but any software update has a risk of breaking some things.

On the other hand, when adding some new devices sometimes the firmware updates are mandatory (but I can't say this is your case or not). If you go by this, you should update.


Have you done firmware updates before (especially for the inverter)?

For the inverter you have to save the settings (and any assistants) before the firmware update and load them back after the update. Read the instructions if you haven't already.

0 Likes 0 ·
Javier Pardo avatar image Javier Pardo seb71 commented ·

Hello again @ seb71.


I have never performed the inverter firmware update. The version is the one that was put on the day of its installation by the installer.


I think I need a special cable to be able to perform the firmware update and I do not have this cable right now.


If the solution is to update the inverter firmware, then I will have no choice but to do it, but I would like someone from Victron to give me a 100% sure answer that this is the problem, since as you have mentioned firmware update could create problems and this is what I don't want.

I will try to contact a Victron technician directly to see if they can help me with this problem, or to see if a technician reads this message and can give me help through this forum.


I am very happy with the system and as I have said before it has not given me any problems during these months. I just want everything to work fine.


Thanks again for your kind help.

0 Likes 0 ·
nickdb avatar image
nickdb answered ·

First step is to make sure you followed best practice properly:

https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom

After this, probably best to get the installer involved, victron don't provide support to end-users, they offload it to the local distributors and resellers in your area.

High voltage alarms should resolve within a couple of days on new installs, after 3 months it is best to check the configuration.


1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Javier Pardo avatar image Javier Pardo commented ·

Hi @nickdb, thanks for your reply.

Yesterday a high voltage alarm message reappeared in the system, which, like the previous time, disappeared a few minutes after reaching 100% load.

Today the charge has been made up to 100% without triggering any type of alarm, so I understand that the problem is being solved. We will see tomorrow if everything returns to normal and there are no problems either, but apparently it was all due to an unbalanced cell as all of you mentioned.


Thank you very much for your responses.

0 Likes 0 ·