Tinbum

Their should only be one BMS that covers both batteries. Change the BMS.

Depending on how old your old batteries are you may need to update the firmware on them.

Are the old batteries charging OK? Did you balance the system when adding the new batteries? Your best off having the new US3000C batteries as master and the last battery. Check the communication cable between the inverter and battery pins is as shown the US3000C battery manual. Re console communication just do a search on here. (Plenty about it)

Just do a search- it's on here.

All in the manuals.

Yes, if you use Batterview and a usb to RS475 cable. Describe what was going on when it alarmed.

Need more details.

Apologies for trying to help. It's actually the US2000B-Plus the author has been trying to update the firmware on.

I wasn't referring to battery view. I'm sure i've seen it on here.

I'm certain their is a link to it somewhere on this site if your search.

Just wanted to check that you didn't think you could only have 8 batteries.

Why are you going to remove the US2000? I'd keep them in.

I cant quite tell properly, but from what you say, it looks as if the order of your batteries may be incorrect which may cause problems. You should be sandwiching the older batteries.

I'm in the UK and it wouldn't surprise me at all if we have it this coming winter.

It sounds as if you have altered a setting somewhere when you tried to set the DOD to 90%. Can you recall what you changed? I don't know your inverter so will let others try to help with that.

You should have one (or a circuit breaker) between the batteries and inverter.

You've probably checked but it not a blow fuse due to high current from charging a flat battery?

I wonder if we are seeing balancing at higher voltage because the batteries are only showing out of balanced cells at the higher charge voltages- that would make sense.

That's interesting, a good lot lower than I'd found and others have reported.. I wonder if its the same for my C's. How did you extract the data?

I have my pylon batteries set to charge at 52.5v as I don't want them only charged to 80% and more importantly I want the cells to be kept in balance. The cell balancing in the battery is small enough as it is, so I wouldn't want to restrict it. Once a week they automatically charge to 53.2v as per the BMS recommendation Unless their is something wrong with the system and its design they shouldn't go over voltage. (I must say though I always use the BMS communication).

Is 52v high enough for charge as I've found my Pylontech C batteries don't seem to start cell balancing until about 52.3v - 52.5v? I've been trying to get exact voltage from Pylontech but they never reply.

Are you batteries C's ? if so ensure pins 1 to 3 are not connected on the CAN cable at the battery end.

What are the led's showing on the batteries?

Be vary careful with voltages. 54.8V will damage the BMS in a Pylontech C battery.

Pylon max voltage setting is 53.2v (at very max 53.5v but not at all recommended) Any voltage over 54.5v will permanently damage the batteries BMS. As has been said before if the CAN is connected the settings should be set automatically. You must check the communication is working by checking the inverter settings in the correct place. I don't have that inverter so have a good read of the manual.