Tinbum

You should always have the newest battery as master. Has that still got the original firmware on it though? (I've not seen 3.0 available anywhere). You said they had offered to take it back- that is what I would do. Did they request that you change the firmware on it or have you done that off your own back?

That seems to suggest its an old chip battery but you say it's brand new so perhaps pylontech have gone back to the old chip. Have you got the other new battery as the master? When did you downgrade the firmware from 3.0 to 2.8?

I'm confused. Having 2 threads doesn't help either. V2.8 would be for an old chip battery not a new one. (Unless pylontech have changed something).

Are you sure those are correct? They don't seem to tie up with current thinking. Perhaps Pylontech are trying to confuse us. it may be worth posting part of your serial numbers that show if you have old chip, new chip or a version we have not yet come across.

Thanks. I'm still none the wiser as to how many batteries you have though. Edit- I see that is in the other thread and here after careful reading.. Your BatteryView screen shots don't look to be of your new battery!! The firmware is 2.8 and release date is 2022. Even if If Pylontech have gone back to manufacturing the old chip batteries again, which I very much doubt, their latest firmware is 2.9. You want to pull the data from the full pack. (I'm not certain on this but it looks as if you are using the HV version of battery view- I've not tried it on LV batteries and I don't know if it's specifically for the HV.) Have you got a new battery as the master?

So many people come on here expecting answers but do not give details of their system. You have now given us more of an idea. You say you are extending yours system and have not given any idea as to what you really have. You ask for firmware for your existing batteries in another thread but we don't know how many- you may have reached the max number, have older types in their as well. What is the production date on the battery?

Please give more details of your set up.

I uploaded the latest firmware from pylontech to the download section a few days ago. Don't think it's changed for quite a while though.

Batteries are designed to go down to 5%. I wouldn't take them that low though.

It really isn't a problem.

The SOC follow the ages nearly perfectly. Pack 2 is very slightly different.

Have a look at https://communityarchive.victronenergy.com/questions/129009/lv-hub-troubleshooting.html very end of the page is best as some debate on dip switch settings.

They will vary. It can be dependent upon a number of factors, eg ages of the batteries, how they are wired, etc. Your batteries SOC will be a lot more accurate than any voltage values due to the voltage curve of the battery. I wouldn't worry.

That doesn't really say a lot- not really an answer. The "battery BMS will not work" could mean it doesn't work as intended as it can't control the voltage, current settings etc coming in to the pack. I'm just really surprised your the first to find this and its not been reported by others so far..

@Quenton Any update?

When I've been contacting Pylontech I've also asked them if they have done this and both times they haven't replied to that question but have to the others. 😒

I have no knowledge on your inverter so can't advise on how to set it up. I always use CAN communication and then the BMS tells the inverter what it wants and the inverter shouldn't get it wrong, though their are a lot of inverters that don't have very good control of their voltages.

I found the problem with the Teensy setup, I had 4 receive mailboxes set as standard and 4 as extended. The 4 as standard were not enough so I added another 4 standard and can now get all the messages. I can confirm that if you send 0x305 and 0x307 it opens up the 0x372 > onwards. (Tried it on my Teensy instead of the Venus Pi). I don't know where the 0x70 and 0x371 come from on that chart but I'm sure it's wrong.

@Youda Here's something nice to have a look at. 2.0.1 in 2021/4/2 is interesting note. So you have to send both 0x305 and 0x307. I've not looked at it properly yet. Pylon CAN bus protocol V2.0.5 20230327.pdf

As I have said, many times, you need to speak to Pylontech. I emailed them last night about something and had the reply this morning!!

53.5v is above pylontechs max recommendation and will in all probability ruin them, especially if the inverter overshoot.